Scott:

** the cylinder heating is much more even on the ground since there is no air flow to speak of.  **

Not really. There are more severe hot spots upon idling or a ground run than in flight. That's why one should ALWAYS keep cowl flaps open when on the ground... to increase the airflow in a poor airflow condition. If the engine is properly baffled that goes away in flight. If it is not properly baffled, all bets are off.

Walter