" jls" wrote in message
...

Leaning an engine takes a little finesse. It shouldn't be done on the
ground unless you're in Denver or on a high-altitude ramp. A small
fraction
of that fuel charge is cooling your heads as it evaporates and flows
through
the combustion chamber and out the exhaust port. Ideally it is rich
enough
to give you a perfect stoichiometric charge plus just a little for
cooling.
If you burn it all by leaning you have lost your mixture's ability to
dissipate heat. In addition, some of a lean charge is burning as it
departs the combustion chamber because a lean mixture burns more slowly
than
a rich one. Damned if I want my exhaust valve to glow just to clean a
sparkplug.

I think you are exaggerating. More than a little bit. I guarantee that even
at sea level you are going to get spark plug fouling if you do not lean your
engine somewhat during taxi -- especially when taxiing in. You just
completed a descent with the mixture full rich and the engine idling -- lots
of cooling and plenty of opportunity for spark plug buildup. I suspect that
the detonation and premature ignition that result from your recommendations
are even harder on an engine than occasionally clearing a spark plug.