AzB Silver Member
Pool has also seen it's share of snake oil salesman with secrets for sale. While some instructors freely share knowledge and it's often excellent, others sell "secrets" that fall into the "buyer beware" category, especially since it may mess up your game.
The secret in pool instruction is to assess where a particular player is at, where they may be able to improve based on their ability, and to have the people skills to clearly and tactfully convey that.
The sentiment you express is true.
Regrettably, there are folks in pool always willing to sell you "secrets." Caveat emptor should be the rule of the day.