Saw a guy on YouTube test a bunch of cheap kits and the metal ones with thicker panels held up way better than wood. Worth checking reviews from people who've had theirs two or three years, not just the first week.

Sounds like the GC just wanted to hear himself talk. A guy who's never been on the business end of a trowel doesn't get a vote on how the finishing crew runs the pour. Lots of old timers say hand floating is the only "real" way, but that's mostly nostalgia for how things used to be done, not some proven science. Worrying about every jab from the office is a fast way to burn yourself out.

Your neighbor got it backwards, fridge slows yeast but bacteria too.