There's a guy I've known for years (because I don't want to talk of other folks the way I do myself, I'll call him Monahan here) with a learning disability; he has very weak short-term memory.
I tend to give him some slack for that - usually. On the BBS, he never even makes an attempt to post to anyone - unless it's to reply to something they said to him. Even then, if he answers in a full sentence, I'm amazed.
Because of my own disability - which I always try to work around - I can't be more forgiving about this. Every few months, we bring it up; every few months, he just says "OK!" about it - then goes back to his same stunts.
Us folks with disabilities try to work around them, because we want to still go on living, go on growing. He won't even try - and that annoys me.
