Question...

So I'm looking at ripping out my Simply Sweet sweater again. I'm knitting it in a variegated yarn, and this is the first time I've used one. I've read that to avoid pooling, you should alternate balls of yarn every two rows. The first time I knit the front, I didn't do that, and the second time I did...so, my question is...when you use something that you think is going to pool, do you alternate, or just let the colours settle where they may?