Well, I don't think, "Hey, I should use C Dorian over this!" either. What I do is just play over chord progressions while jamming, record this jam session, and analyze the notes/scales/chords I used afterwards. After studying modes while practicing at home alone, I just automatically pick the right modes for the sound I'm trying to get without thinking about it when jamming. And, as I was saying, after a couple years of jamming I'm growing away from this modal/scalar playing and I'm striving torwards the sound I wanted to get. This whole post is about how I've realized you don't need the modes/scales, because you can play ANY of the twelve western notes over ANY chord.
"You must stab him in the heart with the Bone Saber of Zumacalis... well, you could stab him in the head or the lungs, too... and the saber, it probably doesn't have to be bone, just anything sharp lying around the house... you could poke him with a pillow and kill him."
- Aqua Teen Hunger Force, The Universal Re-Monster
