> Presumably much of that learning boost is because I'm a hobbyist tier programmer, guessing professionals wouldn't experience the same since they learned this via manual coding trial & error over years.

I can only speak for myself and my not-quite two decades of professional experience, but yes pretty much!

It’s neat to see that sped up for others though with lower stakes, though it’s not quite the same unless you prompt your agent to question you back a lot (Claude is much better at this in my experience)