Increasing Drawing Performance when working with Large Corridors

This weekend I ran into an issue with two large corridors I am working with. One is about 40 baselines with 2-6 regions each, the other is about 60 baselines with 2-6 regions each. The drawing was doing really well- I was surprised. The full rebuild of the entire corridor took a little while, but I only did that maybe twice a day, so no big deal. I expect that. What I didn't expect was lagtime and hangups when I was making grip edits or profile grid view edits to my centerline and transition profiles. We're talking- move one PVI, get the white screen and 20-30 seconds of 100% processor useage. This wasn't going to work. After some messing around, I realized it was the "mini" rebuild that happens when you make edits to a corridor. Now, I work with Rebuild Automatic for my corridors, OFF, but notice in the exhibits below that you get a little intermediate rebuild when working with a corridor. If I grip edit an alignment (or make a change to anything corridor related) the corridor does respond. It takes a full rebuild to get everything lined up again. I figured out that THIS was killing my drawing. So I did an experiement. I built my corridor with ALL baselines and ALL regions unchecked- essentially a corridor of nothing. WOW. What a difference. I might have actually been able to go outside this weekend if I had figured that out!! WARNING- I almost always get a Fatal Error if I build an empty corridor with my corridor surface visible. So I make the corridor surface a no-show style and make sure it is NOT rebuild automatic. I logged this problem pre-SP2, but I don't know if it was addressed.