Schedule a 2 activities network, not tied one to each other by precedence logic but sharing a limited resource.For example:

Activity A – 5 days
Activity B - 5 days
Both activities requiring Resource A of which only one is available.

Most software under resource leveling will schedule A and B at different time, the first one depending on your priorities selection. This is ok up to this point, but the problem is most will show float of 5 days on the first activity while a delay in this activity will delay the completion of your schedule.

Imagine that you as a Project Manager look at the "available" float as per your CPM schedule and start paying attention to those shown as critical and even start moving resources from those showing some float as to keep under control those showing no float. Because most software under resource constrained schedule will show the wrong float for resource critical activities you most probably will end up moving resources precisely from the wrong activities. You either will discover too late it was wrong or start doubting about the CPM float display. Well better start doubting about the CPM float display and either buy a glass ball or software capable of showing resource critical float.

Maybe if your software is not capable of telling you about resource critical float as long as you are conscious of this fact you can still interpret the data in useful ways, maybe it can tell you how much the activity can be delayed if you release your resource constraining, just be careful and always do what if runs before telling your people what is the true available float.

My approach would be to tell them the truth, that float as shown does not means it is available that the only way you have to verify is trough running what if, that better they don’t use any float, that if falling behind better they brainstorm with you about best recovery strategy.

Best regards,
Rafael

May be I am missing the point with this thread. In MSP, tasks have

Free Slack - duration before within the activity will impact on its successor

Total Slack - duration before within the activity will impact on the completion date.

Surely it it a matter of analysing these values.

Also, do a web search, there is trace Logic macro available. This is a very usefull tool, works with MSP2002 and I think 2007.

Cheers

Hi Jacinto,

No, the feature is not available in MS Project, only for "the one" activity as you call it.

It really pis... me of when I have to analyse programmes in depth in MS Project with respect to relative floats, driving activities, etc. so I normally end up converting those programmes into Pertmaster (now Primavera Risk Analysis) and then do it there. It has some really good features for that.

Is "relative floats" possible in P6? Haven’t been able to locate it there yet, but maybe I just need to look closer.

Regards,

Bo

"It doesn`t allow you to go deeper in the analysis."
Such as what?