One good way to catch thoughts is to focus on your feelings. Even if your subconscious is running the show, you know what it's doing because of the way that you feel.
I appreciate what you say, M, about not being able to control thoughts because we have so many. It's noticing them that counts. The way I shifted my thought patterns and energy from negative to positive was through noticing how I felt. If I felt low, I'd stop and become aware of what I was thinking. I'd get caught up in those negative thought ruts (I'm sure you know what I mean!), so I'd ask myself "Is this really helping me?" and switch to something positive. Oddly, it works.
I've had some good experiences with TFT but for me it was reprogramming my brain that turned everything around, and pretty much overnight, too. I've met a few people lately I haven't seen in a while and they keep asking me what's happened because I'm so transformed.