Out-of sequence with twist

This is matter of modeling and interpretation, and the correct method of recording progress, rather than any "fault" of MSP or any settings.

If it was possible to start Task B before Task A was finished, then they should never have been linked FS in the first place.
But of course this situation often occurs.
If Task A, as well as Task B, is a Predecessor of Task C then this relationship should be modeled explicitly rather than relying on via Task B.
Once Task A has started, it has an Actual Start Date, which is an indisputable fact.
Also, if Task B has started then it too has an Actual Start Date, again a fact.
Once Task B is complete it has an Actual Finish Date, again a fact.
These facts should be entered in the Tracking Table.
In MSP, these facts will always over-ride Predecessor links, which is 100% correct. If OPP does it differently, which I doubt, then it is wrong.

In your ABC daisy chain, since Task C’s Predecessor is Task B, and not Task A, there is no reason for the delay of Task A to affect Task C at all (If Task B has started).
Perhaps you need to make Task A a FS predecessor of Task C.

Thanks Trevor,
What you say is quite correct and I see the logic behind this behaviour. However it does not cater for the fact that some of these schedules are being statused by planners and PMs with varying degrees of training and experience. In a recent situation I have multiple PMs statusing filtered pockets of a master file and sometimes in ignorance of the others’ work (geographical and/or communication dificulties). Using my previous example there is a risk that ’C’ may still be delayed by ’A’ and that somehow the tool should alert us to this rather than assume that if ’B’ says it is OK then it is OK.
Wrong behaviour? not necessarily.
Different? Yes.
Which is better? I don’t know but now I know the differences I will be able to work around them.

Thanks again for your feedback, I really appreciate it and understand the benefit of knowledge sharing. There really should be more of it.

It is a bit difficult to see how any software can protect itself from bad input data or any solution for GIGO other than to prevent GI.
A lack of training and experience can torpedo the best plan but at least the lack of training can be addressed.

Trevor,
Very interestingly put, You’re quite right to say that the best method of of protection from GIGO is to prevent GI.
I have used a few different software scheduling packages;
P5, P3, OPP, MS Project and Micro planner X-Pert. Of all of these packages they each have their own small ways of confusing you at times, some more than others.

Paul’s point about the varying levels of training of the people operating software is also valid, as I believe it has led to the way in which these more commercially used packages are being designed.

What I mean to say is, that the amount of selections, bells & whistles on some of these packages is quite astounding. The simple fact is that although CPM can be, and often is quite complex, if there were sufficiently trained people in the industry that knew how to schedule (Not just use software to produce a bar chart, [Gantt - some PM’s and "planners" don’t even know why it’s called a Gantt chart!!]), then I think the software providers could actually stop catering for every circumstance and actually produce a package that could do the job.

Now I know that everyone has their own preference for software, but I like to use the one that I can trust the answers, get consistent results, and is simple to use, will cater for as many situations as possible STRAIGHT OUT OF THE BOX.

So in my very humble opinion, out of the software I have used I rate them as follows;

1st - Micro planner X-Pert
2nd - OPP
3rd - P3
4th - P5
5th - MS Project

Now Micro planner may not be the best known software around, but for consistency and accuracy I have found it the best, and guess what it has a GI prevention system that will not allow you to try and dupe the theory of CPM.

My 2 cents

Andy

Andrew,
Your humble opinion is your opinion and my opinion is my humble opinion.
If we exchange them in a discussion there is some point to having them, but if we take positions and turn it into an argument, we may as well be arguing about our favourite colours.
A person may be in a position to exercise their power and impose their opinion, no matter if it is just plain crazy.
Or maybe not.
Your rating list looks like the exact reverse order of market penetration. Doesn’t that count for anything?
I have seen people who can make a tangled ball of coloured string out of any PM software package. I have met people who don’t even know why they are using the software or what it is supposed to produce, other than PCBs (plausible coloured bars).
Except in some countries and perhaps in WW2, we would not let untrained people and drover’s dogs fly aircraft just because we don’t have enough pilots, would we? If we did, there would be consequences. Same-same re project planning.

Andrew,
if you have nothing to do try a search of Google Images fo "Microsoft Project".
For an interesting jumble of opinions, see:
http://www.disambiguity.com/wheres-the-gantt-gone/

Trevor,
Quite interesting:
MSP 13,300,000
P3 6310
AstaDev PowerProject 191
Micro Planner X-Pert 150
Sciforma PSNext 128
Does it mean something else than pure statistics?

My own rating is:
PSNext,
PS8 (Sciforma)
P3
PM5
AstaDev PowerProject
MS Project
For years, MSProject was my 1st tool as a consultant and software instructor; I am happy that Primavera and Crystal Reports are now #1
Alexandre

I am happy that you are happy.