Judging by a few comments, it seems some would not lean the mixture at a high elevation airport to obtain max power.
Precisely Zoomy.....Glad to see that the thread is returning to the original premise.
A "full rich" take-off at high altitude airports is throwing away performance just when it's needed the most.
Most POH's are quite explicit in the correct use of mixture in these circumstances even though it should be taught as a general procedure.