(snip) tell us how physical training improves focus. I'm almost certain that playing and practicing pool does.
Blood flow, muscle strength, eye health, coordination, overall confidence, endurance, break speed, touch, etc.
2 hours a week exercising, at the cost of not playing pool those 2 hours,* is a net benefit.
Just like exercise does for anyone, chess players, quilters, house painters, copy repairmen, engineers, pilots.
Jeff Livingston
* FYI: During those 2 hours, I do 3 x 2 specific exercises for my shooting arm and bridge and grip, and heart-rate management, so the whole 2 hours is not non-pool.