Well, all I can say is a 3 circuit has been many times over for me the only way to smooth out the transitions for part throttle, and smooth transition. Like someone else said transfer is the problem. Of course you have to work on every aspect of them no matter. You just run out of options with 2 circuit.

As for them gas washing cylinders driving them, that would for sure be an out of the ball park, out of wack carb.

Blowers, and 2 4 tunnel rams make them easier to manage for street driving. A single 4 is the hardest to make work smoothly. Softer signal makes them react more smoothly. Big signal on a single is great for the track but hard to soften on the street. Again, assuming we're talking about something with almost no vac.

The biggest disasters of Doms on the street, is when they're on small cam engines with tons of vac, that they don't belong on in the first place.