A couple developments.

Well, I said I tried to avoid assumptions, but I assumed wrong about the Mac of All Trades policy. A warranty is one thing. A return policy is another.

https://www.macofalltrades.com/return-policy/

"Returns may only be requested within fourteen (14) days of delivery. The customer is responsible for return shipping. We issue a refund less original shipping upon return and inspection."

"If a repair is requested due to a hardware failure within ninety (90) days of delivery, the customer is responsible for return shipping unless an Extended Warranty is purchased...We will attempt to repair the issue; if non-repairable we will issue either an exact replacement or a store credit equaling the full price of the product at the present time."

(Note the use of "issue" as both a noun and a verb)

I conclude that this means I can't return the computer for a refund after owning it for fourteen days. If a problem arises in the next 90 days, I can ask Mac of All Trades to fix it. I would pay the shipping for this heavy computer. I'm not sure who would pay for the repair.

The second point is that the monitor flaw disappeared after I installed Macs Fan Control. I've been leaving the computer on at night to see if the flaw returns, but so far it hasn't. I had been wondering whether the problem was caused by heat. The computer seemed especially hot, but I was unsure if this was a normal result of the aluminum body, which was new to me. I don't know what else to think. If a problem arises, I'll have to fix it. Or debate whether to fix it. Same old story. Hope for the best, expect the worst.

I'm getting more comfortable with the font rendering. I don't regret my purchase. I've enjoyed seeing all the recent software that I had been missing out on. Lots to download and play with. I was reminded again of how much better Mac software is than Windows software. But I suppose that's changing as Apple continues to tighten the screws.