Chuck - 16 degrees PAST TDC??!!
If the Pelican were dead, that one would make him spin in his grave - if he hears it it might just knock him off his Perch anyway!!
I'll put it down to temporary alcohol induced madness.....? See Deakins PP #18 - Mixture Madness.
Ignition happens
BEFORE TDC.
PPP (peak pressure point) occurs about 16 degrees AFTER TDC, as it takes a consistant time for the flame proagation to fully develop.
As for the rest of the topic - FIIK. Running up to 1500-1700 or whatever on a leaner mixture sure does clean oily plugs; never tried the prop cycling thing for that purpose though. Damn sure it does sod-all to the maggies.
