I haven't seen this discussed anywhere. There has been plenty of discussion about the opening with trueshot, but what about mid-fight? If I'm doing something like Mythic Nyth, I can assume I'll have three total trueshots. The opener, one middle trueshot, and then a final 'bullseye' trueshot. Assuming you have a minute or so of leeway, is there a particular situation you look for before popping TS?
I've been waiting for a lull in mark procs to use mine. For example, if I have one and a half charges of sidewinders and about 50 focus, and no barrage or wb to buy time, I'll trueshot so that I don't have to waste focus on a wet noodle aimed shot. Now I'm starting to wonder if I would be better off waiting for a bloodthirsty proc and ignoring all other factors in order to get the crazy haste synergy.
Obviously this is a much bigger deal for the bullseye phase. You're only ever going to get one trueshot off in the bullseye phase. So assuming you just hit thirty stacks of bullseye and the boss isn't going to die for say 75 seconds, you have a full minute to plan the perfect trueshot. What do you look for?