I was about to say something similar, but unless I missed something you've set out the argument pretty good there. I don't think they'd make the old weapons permanently relevant. Although that'd be nice, there's always new content coming out, which would make current gear obsolete and etc. Though when year 2 goes obsolete, they'd presumably be the same as year 1. Maybe they could have a "Legacy Day" or something like once a month when old weapons regain their old stats for a day for old times sake?