This thread is a case study in all the the online home reno archetypes: The Perfectionist, The Dogmatic Professional, The Extremely Certain Layperson Giving Really Bad Advice and The Forum Scold chastising a newcomer. The end result is a mixed bag to say the least.
With apologies to The Scold, I'm adding to this old thread to say that I recently test drove a lot of the remedies proposed here on my first tiling project. Findings:
1. White is the absolute worst grout color for hiding mistakes on imperfectly laid white subway tiles. This is because it creates no offsetting visual interest and it doesn't confuse the eye as to what's a shadow and what's grout. Using white grout after reading this thread cost me $15 and a good hour or so digging it out after seeing how bad it looked. Perhaps it depends on the mistake you're trying to conceal. I had a lot of tiles that weren't in plane and white grout loudly announced them via the interplay of light and shadow. Reverting to the platinum I'd originally planned to use made things many times better. Certain mistakes just disappeared and the overall look was much prettier.
2. Sometimes the no-slivers rule is incompatible with other objectives. I put slivers in one corner because I wanted to start my fixture wall with whole tiles. Since I would never change tile for something like this, the only alternative would have increased the number of oddly sized partials overall and put them on both sides of the wall. I have no regrets.
3. When caulking corners, better to match the tile than the grout. I used white silicone and it enhanced the fold illusion . The dreaded slivers were made far less conspicuous.
A lot of this stuff is just a matter of taste and ever-changing convention, no matter how many tradespeople, made prickly by all the YouTubing DIYers not calling them -- C'est moi! -- insist otherwise. Light gray grout with subway tile should be a rule, though. It's, um, black and white.
With that out of the way, I have to say people here must be really lucky with contractors if you'd ream out someone for the tile job under discussion. I've had far worse luck, which is why I do everything myself now.
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4x12 subway tile
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