Writing code comments has always been hard, because communicating is hard. It's hard to not assume context. It's hard to use the right terminology consistently. It's hard to even put comments in the right spots to begin with. It generally takes me several iterations of rewording a comment to get something I'm happy with. I'll write something lousey that takes 5 times as long to read as it should, and then read it. Then I'll remove a couple sentences, tweak what remains and do it again.