Pedantry
It turns out I'm a pedant when it comes to grammar.
Correcting other people's notebooks, I go into minute detail about which part of the grammar they got wrong, and why other people's corrections are almost but not quite right. I avoid it as much as possible when I think it may just be a question of writing style... until I think that style has crept into "sounding like a non native speaker" territory.
I honestly wish to get the same sort of response to my own notebook entries... When I finally get around to writing them (and when they're not in my mother tongue) so that I can learn the subtleties of the language, not just how to speak technically correctly but so that I sound unnatural.
Am I being to harsh? Should I just loosen up and let small grammatical errors go?