I was going to say the same regarding short URL's, but you beat me to it. I would LOVE if there were a permalink like system for the forums, as I prefer to do my own structure, rather then use a default one or one with low customization.
I understand your logic. However, SEO url's were designed only for search engines, users really don't care how a link looks. I dare you to tell me how would be beneficial for Google to have search results queried and penalize you for cloaking links (same for members).