Using constraint 'as late as possible' for one task delays many ta

[Cecile]

I am using a constraint 'as late as possible' for one task amont many tasks
having a constraint 'as soon as possible'. It delays my project end date when
I just wanted it to delay one task! I can't easily explain, but here is an
example:
Iteration 1 contains:
- Task 1a
- Task 1b
- Deadline 1
Iteration 2 contains
- Preparation 2
- Task 2
Iteration 3 contains:
- Preparation 3
- Task 3
Task 2 depends on Task 1a and Task 3 on task 1b. All I am trying to do is
have Preparation 2 finishing just before Task 2 and Preparation 3 finishing
just before Task 3.
When I use an ALAP constraint on Preparation 2 and 3, task 2 is delayed to
end at the same time as task 3, which is NOT what I want...
Thanks for your help!

 

[Trevor Rabey]

I haven't tried your example, but this has come up before.
The MSP ALAP constraint is very strong, delays all non critical successors
until they are critical.
What's need is a "zero free float" constraint so that Tasks are delayed only
to the limit of their free slack.

Also, remember that all Tasks are scheduled, in general, to start as soon as
possible (allowing for various constraints).
That is, the scheduled start date is only the earliest that the Task can
start.
It doesn't have to start on that date.
If it's not Critical it can start anytime up to the Late Start Date.

 

[Steve House [Project MVP]]

Try using a Start-to-Finish link where the Start of Task 2 is linked to the
Finish of Preparation 2 and leaving everything ASAP. With a link, the
timing of the predecessor task controls the timing of the successor.

 

[Jan De Messemaeker]

Hi Cecile,

This IMHO is a weakness in Project indeed.
ALAP make the task critical and this also (at least one of) its sucessors
etc.

 

[Cecile]

Hello Jan,

Thank you for your answer. 2 follow-up questions for you...
1- Do you have any work-around suggestion?
2 - Do you know if this is something being considered for a fix?
Thank you

Cecile

 

[Jan De Messemaeker]

Hi Cecile,

1. There is no fix as such. Microsoft will tell you that it is not
necessaryt since a Start to Finish link will position the successor just
before the predecessor. But this is "male cow excrement" since when you push
forward the ropedecessor nothing will warn you; Just in Tileme is not
possible in project.

2. This development has been on the wish list of the MVPs for several years
now, even in a high rank. But as I say, when you read MS stuff on it they
deny the problem so little hope of an improvement here.

Sorry.

 

[Cecile]

Hello Jan,
Thank you much for your help, I was very frustrated that I could not figure
it out, now I know why ;-)
Thanks
Cecile