Steve - appreciate your insight as always. Your comments go me to thinking more... and I think perhaps the real way to learn more about the thermocline would be to put an underwater camera down at times when an obvious thermocline is visible on the fish finder. I think that would really help me to understand what is going on.

With my aluminum boat I couldn't really meter around on the big engine and look for broader patterns of fish activity relative to thermocline. With the boat I just bought I plan to do a lot more "metering around". I don't have an underwater camera but one of these days will get one.

This is the kind of stuff I like to investigate and look in to, but I have this feeling that in the end it will prove irrelevant to my fishing. Fishing for big fish my approach is just so much more brute force, process of elimination than it is calculated.

My approach to new lakes is to simply go around to all of the most obvious spots and fish them from deep to shallow. Then I hit the spots that feel right throughout the season. Then over a period of years I learn which spots produce fish. And I learn which times of year are best. Sometimes it narrows down to 2 week windows.

Then I know to go to certain lakes at certain times of year and fish certain spots. And none of that involves looking at the thermocline, the moon phase, or the water temperature. It's just understanding a pattern of fish behavior on a given lake. And that just takes years of fishing to figure out. It also helps if you can get in and fish the lakes when they are good for swimbait fishing vs. after they've been beaten to a pulp (the accurate description for almost every lake in CA now).

I feel like when I go to the lakes now I'm just fishing scraps of what used to be. And I feel bad for the guys just starting out trying to figure stuff out, because frankly you are not going to get much feedback from the bass. Which lengthens the learning curve ... a lot.

In any case I still try to learn more about all the possible factors in case something useful presents itself :) With fishing being tough for big bass now for going on 3 years in nor-cal you have to take whatever you can get and try to milk any small piece of conditional information.