Did the customer actually appreciate you owning it, or did they get more annoyed that there were mistakes in the first place?

Three months teaching it at the library and @mason.margaret still sneaks snacks during my turn.

Honestly this is just the hidden cost of trying to mix work with play when you're remote. The cafe wifi seems fine until you actually need reliability for something important. Same thing happened to me at a laundromat near my place that had free wifi - it worked great for scrolling but the second I needed to send a large file it crapped out. People don't realize the cheap option often has a hidden time tax that ends up costing more in the long run.

Heat treatment is like cooking... it's all about finding the sweet spot for what you're doing." I've noticed that with bread dough too, if I let it proof a little cooler it comes out denser and tougher, just like your chisel. Seems like knocking the temp back just a bit gives the steel more time to settle into a harder state without getting brittle.

Did you try just yelling at it first?