I'm enjoying this discussion. I am 74, with the usual age related challenges. If I'm to continue to swim into my 80's ease is my main mission. This winter I've been pushing gently off the end of the pool feeling the delicious effortless glide then trying to maintain that feeling to the other end. If I achieve a clean well timed catch and rotate and spear against it as slowly as I can and maintain my original long-axis posture and tri-breath with absolutely no head lift I can drift into the far wall with no energy used at all. At risk of attracting correction from the literal (should that be littoral) s2b3, that's how it feels if I get it right. It feels even easier with backstroke. I may win Charle's prize for slow. I know I'm getting somewhere because I looked up to the gym floor this morning to find I had an audience.