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If that is the case, someone should tell those morons in PS and the AH cars they don't know that they are doing.

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I've heard plenty of those cars idle in person and I never said they don't know what they were doing...They sound more like the motor in the posted video than they do the typical over cam'd/under exhausted small block Chevy at the local cruise night that has what's considered a "lopey" idle...and I'll bet you $10,000 that a Pro Stock and SS/AH car's idle will smooth out if you put zoomies on it....

There's a HUGE difference between a slightly erratic idle and what the average car guy considers "lopey"...The reason that a Pro Stock car and SS/AH Hemi have an erratic idle still boils down to exhaust flow....at idle it's just not moving fast enough in the header to get out so the motor sucks exhaust back in during overlap...You can put ANY cam you want into any motor with zoomies and it will not idle "lopey"... and what will actually happen is that with short zoomies the motor will suck in fresh air through the zoomies and run on that air as if it has a vacuum leak so you'll have to shut the throttle blades all the way... Been there, done that...

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I'm not buying your exhaust theory.... even with
open headers my cam sounds the same... and my headers
are made to the engine specs.... over lap causes
the lope

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It's not theory, it's fact....I've done it...

Put your motor on a test stand with zoomies or block hugger, shorty headers and run it and you'll see for yourself...Anything with a "lopey" idle will smooth right out with zoomies, but you need to be prepared to close the throttle blades all the way and it will still idle at 1,200-1,500RPM+ depending on how much overlap the cam has because it will be running on the fresh oxygen that it's pulling in through the headers.......

Overlap does cause the "lope" but because it's sucking exhaust in, correct?? So, the more restrictive or longer the exhaust system is, the more of a chance the motor has at sucking in exhaust during overlap.......your headers hold enough exhaust in them that the motor is trying to idle on it because airflow isn't fast enough to push exhaust out (at low RPM)...once the air speed picks up, the motor smooths out...

If every cylinder has the exact same lobe profile, why does the motor idle erratic if it's not sucking in exhaust??

Have you ever heard a car with zoomie headers idle with "lope"?? The answer is "no" and you never will......