***update*** if anyone cares... My contractor patched a couple of particularly low sections & had a stone restoration guy come in to sand it down. They sanded it wet starting with a 50 grit & went over it two more times with higher grits. I don't know what the final grit was, but they used honing powder when they sanded the final time. The floors are much flatter; it feels like any normal tile floor, except for the edges, where they sort of "feathered" out the sanding toward the border, which didn't really need to be sanded. The only caveat is that, upon close inspection, there are fine scratches on all the tiles. Either the 50 grit was too aggressive to begin with, or they didn't hone it enough at the end. That is a little disappointing, considering that it is a brand new floor (and we are a barefoot kind of family, so it probably never would have happened on its own), but I guess I have to cut my losses at some point, and move on with my life.... Many thanks to bill and mongo for your invaluable input. ...will post pics when the chandelier is hung!

OK, "pointed question" was the wrong term. I guess I view the building department and inspector as my ally in insuring that things get done correctly, even when I'm doing the work myself. They certainly can't see everything. If builders in their jurisdiction are "always using" a method that is very unlikely to meet a safety-related code requirement it should be useful to alert them to that so that they can incorporate checking that among the things that they prioritize in inspections. I'd hope they would welcome such feedback. If it turns out that are choosing to allow a substandard system then my question might become more pointed. I know it is ultimately the owner's responsibility, but most owners, to be honest, don't have a clue, and rely on their builders and inspectors to do the right thing. Third parties who do have a clue can be an important component in keeping the whole system honest and working.

@Judy Frank are the ”saw” marks these textured stripes that run horizontally throughout the planks? my sample board of Finally Mine has them and wasn’t sure if defect of sample or true of the floor overall. Does anyone have experience and insight on these ”saw marks” sometimes I see them referred to as ”cut marks”

That's the floating part. It is supposed to move (expand and contract).