I run my rpm at 2450, mainly because that is where it runs the
smoothest. Most of my local flights are at 20". I fly at 6500' MSL
locally (my airport is at 5300'). Cross country, I tend to run harder
going into the wind and throttle back a bit if I have a tailwind. But
if you want to save fuel, running at low rpm's and high manifold will
get you the most power with the least fuel and save wear on the engine
(fewer total revolutions). I've never heard an argument for different
leaning procedures with high rpm/low mp vs high mp/low rpm though.

My Husky's Lycoming carbureted 0-360A1P has 2200 tach time on it. No
oil burn, good compressions, no metal in the filter. I use Aeroshell
15-50 and change it every 50 hours (along with the filter). I have put
all but the first 250 hours on this since new engine. As I stated, I
lean to 1350 degrees EGT on my one probe. Been all over North America
in my bird. (Just got back from Quebec). Based in Colorado.

I think the main thing is to lean enough to get proper burn, but don't
lean so much as to burn things up. I have some friends with probes on
all cylinders and carbureted engines who have tried to run lean of peak
and they have mostly given up. Just doesn't work on carbureted engines.
It doesn't on mine. Most of Deacons stuff is applicable to fuel
injected, and ususually turbo charged engines being run at HIGH power
settings (like 80% power). It is a technique that uses a lean mixture
to keep things cool. Only works if you have fuel injection, gamis
probes on all cylinders and a fuel flow meter. I don't run that type of
equipment, so I can't really comment on it, though from what I hear, it
does work, if done properly. The guy that asked the question has
normally aspirated, carbureted engine.