Except that it’s not a change to current content. I don’t know that it would cut that much into their time played. I mean, first it only would only make things faster for people who play alts, play those alts in old content, and people who bother to regind old stuff on new alts. I’m not sure how much that adds up.
Like, personally, for most stuff I can’t be bothered to regrind on my alts. So, all the current system does is make me sad sometimes because I no longer have something I used to have.
I suppose there could be the issue of people only worrying about rep one time on one character in new content. That could be an issue, I agree. Maybe make rep account-wide the expansion before the previous expansion. For example, when SL launches make Legion and older rep account-wide. I doubt many people will ignore current rep because they know it won’t matter as much in like four years. 