I have an incredibly nice semi-hollow gibson (with a balsa block). It's beat up - but the sounds are incredible for jazz, retro, and some forms of country. THe best I've heard. I would very much like, though, for this to be my main guitar and want to add some variety to it - so I'm thinking of routing in a middle pickup - a texas special fender (wired to bridge sounds) so that the configuration is humbucker-single-humbucker. I have been told a couple of times that the routing PROBABLY shouldn't affect the other pickups or materially affect the guitar's structure as it relates to sound. I don't really care about collectability, long-term value, aesthetics or anything like that. Just don't want to ruin the sounds of the other pickups. I'd be eager to hear your thoughts if routing in a middle pickup affects the sound of the other pickups substantially? THanks for any advice.