As long as there is a 2" overlap, am I ok? That's the whole (not so secret) secret to the system. So long as you maintain that overlap for a continuous membrane, nothing will get through it.

I've been going back and forth on this same topic for the white ceramic subway tile I'll be installing as a backsplash in my kitchen. I'm using a 2"x4" mosaic. The problem is they don't make matching bullnose pieces. I can get them in bigger sizes and try and cut them down with a wet saw, but they're thicker than the mosaic (1/4" vs. 5/16"). I'll have some areas where the edge of the tile is open (i.e. doesn't terminate into a wall or cabinet). For those edges, I really just want a matching 2"x4" bullnose piece with the bullnose on the short edge. In the upper corner, I want a 2"x4" bullnose piece with a bullnose on both the short and long edges. For the top row where it's open, I want 2"x4" bullnose pieces with the bullnose on the long edge. I looked at the Schluter, but I really didn't like it. I'm going for a more rustic look, and I think it has more of a modern look. The solution I finally found was a place down in Cincinnati where you send them pieces of your field tile and they make them into bullnose pieces to your specification with a kiln fired finish. That way everything matches my field tile. It's costing me about $4 per bullnose tile, but it's giving me exactly the look I want. I think they have a minimum order amount of $50.

I wouldn't install the shelf or even attempt it. And I have a downdraft, not hood - also an electric stove not gas. Clearly not a perfect kitchen, but I do well to get the grease/steam spots off the subway tile behind before they've turned in little yellow greasy petrified dots that must be loosened one at a time. I'd never keep up a shelf. I don't know what I'd use there that I could expose to any additional heat or steam from boiling pasta anyway.

We didnt get the corner ones, got tge rectangular, white to coordinate with tile. i like them better than my ptevious tile ones because the water drains out. and they look nice