I got smart today, and realized that a lot of worry about the straightness of my rows could be easily averted by using my laser level. (Previously I was using my 36" level to manually check a section at a time.) I also upgraded from a premixed product that called itself a thinset mortar to a real mortar, around concerns it wasn't as strong. (And indeed it seems to have a bit of flexibility in it, which may be good for longetivity but bad for moisture.) In case I haven't called it out enough, check out the awesomeness of the laser below:
I kept going, mostly because I thought we needed all the tiling done (but not necessarily grouted) to do the final trim on the plumbing.
And finally, there had been some debate about whether we wanted to run the black border around the ceiling of the shower (so if you look closely in the Day 30 photo you can see a space at the top). Well we decided not to, and so I filled it in with a white tile: