can I get away with not filling these gaps at the top and edge of new drywall, which I shall be tiling directly upon (after priming). What is the usual procedure for tiling up to the ceiling, use caulk? (as grout would disappear through the hole!) or edging strip - which I think can look naff.
I'm going to re-plaster (or hopefully just patch up) the ceiling, so I could try but wondered how much you can get away with behind a tile