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Critical Chain Vs C.P.M

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Sivaruban Sivapra...
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I have read about Critical Chain using buffer management and the benefits of using critical chain compared to CPM.My question is has anybody used CC or implementing CC for their construction project .Is CC only suitable manufacturing and software development. There are some PM Tools that have this feature and PMI U.S have acknowledge Critical Chain as a better system than CPM.

Siva

Malaysia

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I attended a seminar on this (actually they were talking about the Protocol), when one of the speakers talked about what he promised was a better way of scheduling by using C.C.
I did a quick survey among fellow participants at the end of the seminar, most of them felt that the speaker was waffly and copied his notes from books.
Guys, dont waste your money on these seminar nonsense in future.

Paul Cunningham, Hong Kong/Singapore
Bernard Ertl
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The last time I read up on the Critical Chain method, the papers were riddled with jargon such as “evaporating clouds”, “self-reinforcing negative feedback loops”, “bad multitasking”, “leverage points” and “buffers”. What I got out of it after distilling it into laymans terms was the following (if I am wrong, somebody please correct me):

  1. Estimate tasks / activities without any fat.
  2. Create a well defined (well connected) critical path schedule where all logical (hard) dependencies are specified.
  3. Resource level the schedule.
  4. Add “buffer tasks/activities” (fat) to the critical and near critical tasks so that you don’t
    commit to the true (lean estimate) critical path. The fat will shrink as the schedule slips.
  5. Implement a feedback mechanism that keeps everyone informed of the progress and changing criticality in the schedule.
  6. Establish clear priorities. Ensure that workers finish one task before starting another.

Of the above, the only items that are specific to Critical Chain is the addition of the "buffer management", which to my mind is the same thing as float management in CPM except for the fact that you actually may build some fat in your critical path schedule.

Personally, I prefer to schedule without fat and manage the project to the most aggressive objective. It would seem to me that building fat into your schedule is just setting yourself up for Parkinsons Law, "Work expands to fill the time available."

Bernard Ertl
InterPlan Systems Inc. - Project Management Software, Project Planning Software
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What I ment was, PMI seems to silent on this issue, or I have yet to read about PMIs stand on this issue, but if you go through PMI database about CC there is a lot of write up in PM Journal, Network and other papers presented at PMI fourm quoting the CC is better management system compared to CPM.
Check it out
Bernard Ertl
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[quote]PMI U.S have acknowledge Critical Chain as a better system than CPM[/quote]

Do you have a reference to support this?

Bernard Ertl
InterPlan Systems Inc. - Project Management Software, Project Planning Software