I played against a thresh support paired with miss fortune yesterday as graves with a leona support, never really felt under pressure in lane. He telegraphed his jungler's (blitzcrank... lol) position with lanterns so they never really got any crazy ganks off. Was reasonably easy to bully him away from souls.
I still think he is best suited for the jungle, you can push him out of lane too easily and when he isn't using his lantern to collect souls you know you're about to get ganked so you can just hang back a bit.