I agree that this feat, if published, is idiotic. I think, however, that in any system which features a near-constant stream of supplementary materials, you just have to accept the fact that at some point, somewhere, some incredibly stupid thing is going to be published. When that happens, you ban it and move on.
My high school band director used to complain that if a show went perfectly, nobody would say anything; but after a disaster, he'd hear no end of it. As far as 4e goes, I'm glad that splat book idiocy is limited to just a handful of things. If WE is the only bannable thing in PHB2, I'll call it a job well done.