Well there are no rules and I wouldn't be surprised if some people have been doing that - the sudden surge in XMR just looks a bit odd to be honest.

I think we have enough people to be able to win without resorting to such measures though - we just need to get people to vote.

According to SteemD: We have 6791 accounts active over 24 hours and 15,300 over 7 days.

Even if we exclude bots and multiple accounts I think if every person able to vote did we would wipe the floor with everything.

The problem is just reaching enough people in time - not everyone uses Steemit every day and not everyone has a Twitter account.