That thermocline business is junk science. When it comes to catching fish, that is. Theoretically the most active fish can be found there, but that absolutely does not mean that the guy with the biggest sack of fish last weekend, or this coming weekend will have caught their fish there.
It also doesn't mean that if you find a brush pile on a ledge that is dead center within that column of water that you are unlikely to get skunked fishing it.
So there ya have it. Looks good on paper, and sounds great in magazine articles and seminars, but it is complete bullbutter. 😊