Interesting question.
Dan Duchaine use to mention once you got out of 10-12% bf. range, it was time to drop weight. His reasoning was that even a fit big guy at a bit higher percentage will look like a lump of crap at those percentages.
I think you can go a bit higher than that(I had my best size/strength gains in the 14-16% range), but I think it right not to perma-bulk in most cases, dieting simply eats everything away.
The one case I think It is warrented is if you want to get your strongest naturally, 99% of the really strong natural powerlifters I've seen had to let themselves become messes at 1 point to get there.
In your case, I'd simply run at a 500 cal. def. for a few weeks.