What do you think of this technical pitch? BS???

I have seen that.
On an engine with a jumped timing chain at low revs. On an engine with very late ignition timing and a partially restricted exhaust.At mid revs
On an engine with a severely restricted exhaust, again at low revs.
On an engine with pumped up lifters at maybe 4000 or so rpm.
Of course 2-cycle marine engine engines do this as a matter of course.
And there were certain superbikes in the early 2000s that had a problem with this at higher rpms and the factory built special air boxes to handle it.
It seems to me, the devil is in the details.
Ima thinking for us regular old-school guys, with well-tuned combos,Especially streeters, we probably don't need to worry too much about it; at least I'm not gonna.
Oh yeah I've also seen snowmobiles do it. Mostly 3-bangers with the PTO cylinder fried.heehee.
But 2-cycle piston-port engines have always had trouble with that. Rotary valves, only when the disc is on wrong, and reed valves only when the reeds are done. But yeah, piston-port engines do that all the time. Their air boxes have drain holes,heehee.And have fun tuning them with the airbox or velocity stacks removed.