Erm, fromthe original post;
"Lets say after several years use the compressions decrease to low 70's."
This does not refer to compression checks? What would you suppose he meant by "low 70's"??????
"But I am arguing that if wear-induced leaks cause cylinder pressure to be reduced in a running engine, then this will cause a reduction in power output."
And while you may be technically correct, it is a moot point.
In most cases the reduction in power output is insignificant. No reduction in horsepower. The TCM test data support this. Where did your data come from?