Actually, you're describing a voting ring, which is against the rules and is bannable. Luckily the software is intelligent enough that it detects people who do such things and automatically nullifies the effect of those votes.

I guess so. I should clarify I've never actually done this, just seen other people [say they] did it. And watching the vote patterns correlated with homepage position on my few submissions tells me it would work.

BTW I don't see any mention of this in the rules.