How can Dual Wield not be stupid? Ive never seen a game pull it off well, let alone an RPG. Its stupid, because its more trouble than its worth, and could well just leave to further problems.
I will say that it was amusing in the Marathon FPS series..... but, of course, you're a cyborg super-soldier in those games, so there's alot less issues with strength and coordination problems. And, of course, that was back in the day of "traditional" FPS's (unlike the modern longarm+sidearm style) that didn't care about carrying 9 guns or the mechanics of reloading them.
That said, I really don't care about it in Fallout. Haven't really felt the need to go all John Woo and leap through the air with my twin nickel-plated 45's. (Which reminds me - see the "The Other Guys" movie posters for just how silly that cliche seems to be in the modern era. We want to add this to FO:NV why?

)
Edit: interesting. Searching for "dual" in the Nexus mod site doesn't return any dual-wield mods. "Twin" "two gun" and "John Woo" didn't either.