Well, it's probably for a few reasons. Performance and removing failure points.

 

I suppose that I could just use the vacuum reading on the boost gauge to get an idea of where it is starting to vent. As it is now with the stock ABV, I can hear it venting boost at very low vacuum just where I'd kind of like it charging a bit of boost pressure such as holding light throttle around a corner but wanting full boost as soon as possible coming out of it. I run into this at our local autocross events as we always have one or two tight apex turns.