I always write primarily in "second person" and not a single person has cared, though 95% of my partners write exclusively in third person.
It has a huge advantage in same-sex two-person role-playing so you avoid ambiguous "his" and "her" without having to long-windedly name/describe the characters over and over, and I don't see anything wrong combining "your" with third-person style descriptions of a character when it can add flavor. It flows fine and is grammatically sound. You're not co-writing a novel together, so unless you're some weirdo who goes around showing everyone their ERP chat logs, it makes no difference.
The best way I have to explain writing in second person is not that I'm some weirdo who confuses the player with their character, but that I'm directing a post towards that character. I image three levels of interaction, OOC (talking player to player, something I avoid 99% of the time), IC (the "don't metagame me bro" level), and Pseudo-IC (who we're pretending to be, and how I'm going to be interacting with anyone who contacts me on a sleazy role-playing site). If you're the kind of person who has no investment like that in to their character at all and just says "hi wanna rp let's talk about a scene?", no passion or flirting, then you just come off dry to me.
After all, role-playing IS about pretending to be someone you're not. It's probably more natural in furry circles where people attach themselves to a fursona, while also potentially playing instances of it as a character when role-playing.
On the other hand, if someone were to try writing first person at me, It'd feel immersion-breaking for reasons I can't explain exactly, and maybe that's the same feelings I'm giving to other people.