You obvioulsy haven't flown helis long, it's fairly common for the starter shaft bearing to go on some models, likely because of the direction force is applied with the starter. I can't say it's very progressive, one minute it's ok, the next you spin the bearing.

And... w/o mincing words, the most common source of interference I've seen is metal noise (broken header, loose muffler bolt etc.), often more progressive but, still very detectable. The next most common source is another Tx on the same frequency. Neither is very progressive in nature and PCM has better noise rejection so, you can maintain control under conditions where the ppm unit would be nothing more than a random movement generator .

I agree that a newbie might be confused by the slow reaction intermittent problem but, you soon learn to listen to that feeling that "somethings wrong". If you're in doubt about your ability to detect the 'progressive' type problems, invest in a glitch counter. More accurate than the "I don't think I commanded that hiccup".

AND... it's not about saving the aircraft, it's about saving lives.

Oh, and Roger, I don't hink we "crossed paths", I'm just not convinced one way or the other on IPD. I just need something more quantifiable than a marketing claim that it works better.