I think it would, because it might reduce the amount of time spent in open loop. I hit 5-6psi easily at half thottle while accelerating. I believe that pushes it into open loop and dumps fuel.
It wouldn't limit boost to anything lower than the normal wastegate pressure though. So I think it would still go to 5-6psi at partial throttle, but if you have your max boost upped to 12 or so I could see it making a difference.
True, I was thinking of something else. I have been thinking about designing a hydraulic wastegate accuator that's controlled buy a server. That way you can have 0 boost all the way up to whatever you want.