Look at the ET from the 650 DP on 425 cubes and look at the vacuum it generated @ WOT. It ran the quickest ET and highest MPH. Surely it was choking that 425 to death......
You really like this article, you found one instance that backs your theory up, how many go the other way, unfortunately the only real way to know test a few different carbs, I'm sure once the OP gets his carb setup he'll be satisfied.