Sorry for the arse tissue issue You seemed well over confident there at once...
Sweden is a nice country, eh? Because here i have had the pleasure of sitting in one of these cars, the S4, looking at the hardware up close. The way I have explained it is the way that Abarth meant it to be.

The diagram actually shows what im saying there... The valve opens at a certain boost so that the supercharger wont be straining the turbo at higher boosts.

The "RACE CAR" as you describes it aint that much racing anymore according to me, as he just made turbo-lag worse for himself.