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Driven predecessor in critical path

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Lo Gary
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Dear all readers,


In Microsoft Project 2007, there was a function which enable us to know which predecessor out of other predecessors is driving the critch path, this function is no longer exists in later version.


Could anyone teach me, if I want to squeeze the critical path, and I trace back from the completion date backwards. However . some task have many predecessors and could I know which one is driving rather than I have to squeeze all predecessors.










Tom Boyle
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Gary,  Look for the "Inspect Task" command (in the "Tasks" block of the Task Ribbon), which opens the Task Inspector pane.  The "Predecessors" listed by the Task Inspector are the driving predecessors for the selected/active task.  Each driving predecessor is provided as a hyperlink, so you can use it to jump back from task to task through the driving logic path.  These calculations are independent from the "Critical" flag; you can trace the driving logic path for any task regardless of its criticality.  For MSP 2013 and later versions, also look for the "Driving Predecessors" bar style on the Task Path menu of the Format Ribbon.  That bar style graphically depicts the same trace.  That's the good news.   The bad news is that MSP's internal calculations of driving logic can be quite wrong under many real-world conditions - (Problems with Driving Logic in Task Inspector and Task Paths (Microsoft Project 2010-2016)).  During crashing exercises, these can lead to a focus on shortening tasks that ultimately have no impact on the project completion date.  Besides computing drag, the BPC Logic Filter add-in that Steve mentions includes its own Task Logic Inspector that offsets these issues and provides a bit more functionality.  Good luck, tom
Stephen Devaux
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The "driving" predecessor of a critical path activity will be the one that's critical, i.e., the one that has critical path drag (unless you've used a scheduling constraint).

Additionally the drag of the critical path activities will show you where you might go to "squeeze" the critical path and by how much. Tom Boyle's BPC Logic Filter is an add-on to MSP that computes critical path drag.

Fraternally in project management,

Steve the Bajan