Tearing out my masterbath next week.Trying to work out a detail that has been buggin me. Walls are plaster with tile up to 48". When I tear off tile I'll be left with some pretty nasty wall conditions.

My plan is to install drywall up to 48" in the dry areas where tile was before, excluding the tub/shower surround? I'm not re-tiling the walls, only in the shower. At the joint where existing plaster wall meets this new drywall will be an uneven joint. Would a chair rail be appropriate to cover that joint, or is there another method? I cannot run the risk of having it split and crack.