Thanks, Michael. As I said, I don't use SplitPV's so it hasn't been on my radar to learn or figure out. But while I'm learning so much today, I still haven't seen why using a homemade PV style vs a stock style helps any of this.
As stated, some of the stock profile views are set in such a fashion...that they are NOT dynamic, with regards changes to the PGL. And when one drags any design element BELOW the calculated datum the grid does not adjust and the design element line is CHOPPED OFF.
Monkeying around with changing the setting from USER specified to Automatic...sometimes cures this, other times not.
As such I advise against using the stock profile view styles. That being said, having encountered this undesirable behavior since the initial beta release, I can honestly say I have not tested to see if this is resolved in 2010/2011; although I'm a little skeptical that it has. because I'm certain that Adesk would consider this behavior 'as designed' and not as a flaw or defect so most likely would not have altered their functionality.
Aditionaly I have found that by not using any of the stock styles for anything, one learns C3D faster, and has a deeper understanding of how and why things work, or not by setting up all styles from scratch. As they say YMMV.