Hmmm. The last part of my reply didn't get posted. I might have deleted it or something. Anyhow, I also wrote that Jolly tiles can also refer to tiles with mitered edges. That allows two jollys to turn a corner. So the term can be used in different ways. I'm not enough of a tile guy to know if one description is more correct than the other.

The profile is not even resting on tile properly in the #3 pic regardless who bought it A few hiring tips for anyone reading , Always ask the prospective tiler whos going to install, is it you yourself or do you send in the B team , the C team etc. Secondly you will know when you have a tile pro in your home, they will start getting less and less interested when you start declining having them order purchase and supply every last bit of tile related material for the project its not always about profiting or markup but more about risk and having a smooth project , this also puts the liability in your favor when things backfire vs attempting to shave a cost. One must ask themselves if they know enough about the tile business to be qualified to guage the prospective hires "knowledge"as well as select and purchase the correct materials . There is so many new products, methods , industry standards and a million hacks out there coming in with low rates willing to engage in sharing liability be very careful in the hiring process. @OP youve got the C team and i think the B team is on vacation here

why not just do the bullnose? And perhaps go w/a 4x12 instead of a 3x6. here's my shower. I used a 4x12 with bullnose on both the vertical, for outside edges, and horizontal, for the top row the bullnose option is one of the cleanest looks you'll get the schluter I did for the accent and the niche (I chose black) close up of that same 4x12 tile but in a diff layout. (this is my neighbors shower) we opted for a stacked pattern layout. slightly more modern looking this one got the Schluter edging on the outside In this one, the tile didn't come w/a bullnose edge. we went w/the pencil liner. again, a larger tile (either a 3x12 or 4x12) and a stacked layout does this give you a better of idea of what look you like?

I used solid-surface material for the edges, same as used on my countertop. The fabricator handled this. The first photo below is a close up of Schluter edging (not my bathroom). The second photo shows edging with Caesarstone Blizzard on the niche and window in my master bathroom. And the 3rd photo is natural quartzite, used in my guest bathroom. Same stone on countertop, vertical edge of shower, curb, edge of shower niche, and edge of window. This was before the shower trims, shower head, and glass enclosure were installed.