The mistake is assuming that because it works for you it will work for others.

I think I'm unusually disrupted by spelling/grammatical errors. I find it extremely hard to read the occasional posts here that use e/em/eir or other gender neutral pronouns instead of he/him/his for example but I assume this is unusual as I haven't seen anyone else mention it. I find it sufficiently distracting that I will usually give up reading a post that does that.