I've come across this dilemma quite a few times at INCAT.... A customer is migrating from 2D AutoCAD to Inventor (finally) and the question comes up to if they will re-model some of their existing AutoCAD data into Inventor. More often than I like to hear, the answer is NO, we can't verify that our AutoCAD data is accurate. Over-ridden dimensions are mostly to blame for this answer. It seems it is much easier to edit a dimension to the length that you want it to be rather than go through all of the hassles of updating all of that non-associative geometry (I smell trouble). My Dad always used to tell me "If you can't find the time to do it right now, how are you going to find time to FIX it later?"
Inventor to the rescue! Although it won't compensate for the fudge factor your colleagues choose to use in AutoCAD, Inventor WILL adjust imported dimensions to the correct dimension that the geometry is drawn to.
Check this video out of some changed dimensions in AutoCAD and how Inventor "repairs" them to what the geometry reflects....
http://screencast.com/t/SqQYAt4t
Hope that helps,
John with the INCAT CAD geeks
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