Oh, that's easy: I think you should feel a little uncomfortable telling someone else you think they're being misleading, because it's another way of saying they're being deliberately deceptive, which is not something you'd say to their face.

I'm sure it's something I've said too, and if I was called out on it, I'd like to think I'd agree and amend my comment.

It is a little strange to call that point out as "ad hominem", for whatever it's worth.