a new way to rate engine power

That's correct, you lean out the mixture once you reach level flight, in order to get the best efficiency. If your aircraft has EGT gauges, you run the mix at either "rich of peak" or "lean of peak". Which way to go is kind of a debate that goes on among aircraft folks.

When the mixture is "leaned", the amount of fuel is reduced, and the Exhaust Gas Temperature (EGT) rises to a "peak" value. "Rich of peak" refers to a number of degrees (25, 50, 75, 100) on the rich side of peak, while "lean of peak" refers to a number of degrees leaner than peak. The procedure is to set the engine power and begin leaning slowly to peak EGT, then adjust for the number of degrees rich or lean.

Without an EGT indicator, RPM is the only indicator available, and it cannot accurately be used to control mixture in the absence of an EGT. To avoid damaging the engine using only RPM, my rule of thumb for leaning was to lean to max RPM and then just a bit richer.

 

I'm sure it is a waste for some.
I'm sure you guys know "THEY" ridiculed Galileo and imprisoned for suggesting the earth did indeed rotate around the sun and that the earth was not flat. "THEY" thought Thomas Edison was goofy, "THEY" said Einstein was a wack job and "THEY" told Bill Gates his idea wouldn't work. "THEY" also gave Tesla a raw deal for his ideas. You see "THEY" just didn't understand.

Now I'm not comparing my ideas to the quality of above memtioned folks in any way here.
But I will tell you that you guys fit in perfectly with the "THEY" I mentioned.

Happy new year !