Hmm seems thats pretty much what I just said? The level of problems with the loss of muffler pressure depends entirely an all the factors I just listed that's a fact. Also keep in mind the earliest commercial Saitos (.45) came with no muffler pressure tap at all on the short stack. However if one looked at the size of carburetor venturi you would see that it was is choked down far smaller than similar displacement engines to provide more fuel draw.
John