I'd be tempted to mount a gopro and light right over the carb and make a good pull to see how the throttle openings are behaving during a hard run. Might shed some light or might just be a stupid video.
Ha ha...oh man, what is it they say: "great minds think alike"...yes??? LOL
I dusted off my trusty Hero3, re-charged and just need to get a slightly longer air cleaner stud so that I can precisely position that little rascal right over the secondaries...but you bet, absolutely on my TO-DO list!!!