Well, you bring up a good discussion topic. I work for engineers that use alot of top down design and prefer using it for his own functionality. You really cant argue with their methods, it works well for them and saves them time.
Two thoughts:
learn to live with created dimensions (cringe)
teach patterns and pattern table functunality
if you dont want someone to do it, couldnt that be written in the .sup file ? rather than leaving it to the user to allow out of scope?
The pain I have is , if just redefining the mounting holes (main ECG canidate) you must specify primary surface in order for the hole. You cannot go in and redefine just the two linear or axis references, which allows you to see the correct measurements to your selected references. You must select a primary surface for regeneration which makes you loose your correct hole placement.
Good Post, you win a Phatt Award