PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

Aka

Float and the Cheshire Cat

The smile is there but the cat is gone

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

The 1st thing you need to decide is

whether Earl IS crazy

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

If YES

and you do not want to psychoanalyze me

then your time would be spent elsewhere

and you are excused.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

4

The Evolution and Demise of Activity FLOAT

If Earl is NOT crazy

Let’s examine these crazy statements

that he is making about Float

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

5

The Evolution and Demise of Activity FLOAT

Float – A BANKRUPT BELIEF

Activity Float is a MYTH !

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

6

The Evolution and Demise of Activity FLOAT

The original paradigm of a Critical Path

and the ‘floating’ of activities is no longer a valid concept !

Why Not ???

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

7

The Evolution and Demise of Activity FLOAT

H I S TO R I CAL B E G I N N I N G

The limited ‘special case’ of the first project

scheduled by the Critical Path method

is no longer the real world of scheduling.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

8

The Evolution and Demise of Activity FLOAT

The Kelley-Walker development which used

activities chained into sequences

only used activity durations and

their logical relationships or sequences

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

9

The Evolution and Demise of Activity FLOAT

With only a base calendar and no date

constraints the analysis was free flowing

and open ended

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

10

The Evolution and Demise of Activity FLOAT

Hence, the chain of activities which

determined the total time needed to

complete all of the work was the answer to

the problem they were solving.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

AKA the Critical Chain [Dupont]

or

Critical Path [DOD]

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

12

The Evolution and Demise of Activity FLOAT

Those paths which were not said to

be determining the project’s end time

had more time to accomplish their work

without affecting the total time were

said to have slack or float time.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

13

The Evolution and Demise of Activity FLOAT

E V O L U T I O N

From 1960 to 1975 many additional

attributes were added to the network

analysis system:

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

14

The Evolution and Demise of Activity FLOAT

– Multiple Calendars– Time/date constraints– Multiple resources– Resource Allocation scheduling– Durations [lead/lag] on

dependencies– Multiple projects

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

15

The Evolution and Demise of Activity FLOAT

T H E E F F E C T ?

Activity performance time was now

segmented according to the availability of

resources, work calendars,

andimposed time/date constraints.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

16

The Evolution and Demise of Activity FLOAT

T H E R E S U L T ?

A continuous time path does not exist !

Therefore, the computation of Activityor Total Path Float while

mathematically possible is not realistic and the utility

of FLOAT becomes misleading.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

17

The Evolution and Demise of Activity FLOAT

The actual path[s] become invisible.

Like the Cheshire cat,

the smile is there but the cat is gone

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

18

The Evolution and Demise of Activity FLOAT

Instead of a ‘Critical Path’there is now a

Critical Sequence

and is the ‘longest path’which may or may not be continuous

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

19

The Evolution and Demise of Activity FLOAT

But, why do we need to know It ?

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

We don’t

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

21

The Evolution and Demise of Activity FLOAT

Once the work plan and schedule

are accepted as the ‘plan’

our attention should be on executing the

work according to the plan

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

Plan the Work

then

Work the Plan

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

Once the plan for doing the work is set

IT CAN NOT BE CHANGED !!

Why not ??

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

The work plan of dates for the start and

completion of all activities and milestones

have been developed based on many

variables.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

The network of activities is actually a very

large number

of simultaneous equations of activities with

time,resources, and calendar variables.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

26

The Evolution and Demise of Activity FLOAT

Change just one variable

and

the analysis becomes invalid.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

27

The Evolution and Demise of Activity FLOAT

Whoa, wait a minute

We enter actual dates as work is performed

Doesn’t this invalidate the remaining

schedule ?

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

N O

Why not ??

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

Because we are working the Plan

Not re-planning the work !

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

Once activity actual finish dates are entered

those activities are no longer used in the network analysis

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

31

The Evolution and Demise of Activity FLOAT

Is all well ?

NO ?

Why not ?

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

32

The Evolution and Demise of Activity FLOAT

The network analysis will compute

new dates without rescheduling the

resources.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

Is this OK ?

NO !

Why not ?

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

The Plan included the activities of many

diverse performers such as sub-contractors,

suppliers, external agencies,

and interfaces with other projects

especially as to their resources

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

And these participants have

other projects they are working on.

Hence, the plan must be fixed and

performance managed to follow that plan

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

C O N C L U S I O N S

Activity Float and Total Float have become

irrelevant and misleading to those

executing the Project work.

To focus on it is a pitfall and booby trap.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

R E C O M M E N D A T I O N

Once the work has been planned and

scheduled ,

status reports resulting from the input of

actual performance and progress should

have the Total Float values suppressed.

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

COMMENTS FROM REVIEWERS

I agree completely with Earl. “Float” is a term planning ‘types’ like to use but working people just want to know when can I start? And when do I have to finish?

-- Robert Youker

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

COMMENTS FROM REVIEWERS

You are right on the money.

-- Abhi Basu, Basutech

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

COMMENTS FROM REVIEWERS

I love the way Earl is able to stir us up to do what I think PMICOS should be about –

the recognition of the manner in which practice is often in conflict with theory and an effort to explore that conflict for the good of the profession

-- Gordon Davis

PMI College of Scheduling“PMI” is a registered trade and service mark of the Project Management Institute, Inc.

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The Evolution and Demise of Activity FLOAT

Earl Glenwright, SME, PSPA.S.S.I.S.T.

P O Box 3305Eagle, Colorado 81631

1-970-328-3131Earl_BG@ yahoo.com

Assist_BG @yahoo.comSofia/Bansko, Bulgaria