I did that on one of my first batches, a red ale that I added maple syrup and raspberries to (and that I absolutely abhor, but that's a different issue). I invested in a pair of 3-gallon carboys so that the head space wouldn't be too extreme. Cut the priming sugar in half when you bottle. Really, there's nothing too much else to it, it's a good techique for experimenting with different additions, or maybe dryhopping a later batch with different varieties, etc. Nothing really more complicated other than the concern I had about headspace had I used 5-gallon carboys.