Simply put, what enemies in game can Maya Thoughtlock? I know she can't thoughtlock bosses, but are Constructors included in that category?
Thoughtlock works on anything that can be "held" with Phaselock (anything that doesn't take direct damage instead of being levitated). So most bosses, large enemies like Drifters and Constructors, Buzzards and others. If you can't Toughtlock a target it will take damage from the Phaselock instead just like from a normal Phaselock. It can however affect the majority of Badass/Super Badass enemies just like Phaselock, making them very good targets.
One thing I'm unsure of is whether Sub-sequence will target "unholdable" targets which seeking a next phaselock target. In my experience it won't, but it's hard to tell since non-phaselockable targets are uncommon.
I think all enemies that used to be grappled by the old phaselock are affected, that excludes constructors. one nice trick: thoughlocking surveyvorbots makes em heal you.