trying to tie SC and turbo behavior together is a faulty exercise. Without delving into anything technical to explain it, it can be visibly seen in this example:

Pace a loaded semi up a big hill on the freeway and listen. He won't downshift, maybe won't even move his accelerator pedal or pick up the rpms but as his engine works against the load of the hill and the exhaust temps rise, you'll hear his turbo spool more and more. A SC is never going to do that.

My point is that my experience with my turbos cars (only 1/2 dozen old turbo dodges and now my TT383 in the fury) is that it takes a big hill in order to go into boost. It is pretty easy to get my Fury from cruise @ 20" vac to 'preboost' @10" vac and start to hear the turbos spool up, but I don't go into actual boost unless jab the throttle.