Is collusion profitable in STTs?

[KCW12]

I've been thinking about collusion between players sharing hole card info over the phone or IM, but is this actually a losing tactic in STTs? I've had two conflicting thoughts about this one. Assume the two colluding players are sharing hole card info, avoiding showdows with each other, dumping chips, etc., basically trying to maximize their total equity depending on the situation. They agree to split the profits at the end. Here are my two conflicting arguments:

- This is profitable because the other 8 players are losing equity by playing with the colluding players, thus the equity lost must go to the cheaters.

- This is not profitable because the colluding players are paying double the buy-in for the chance to win the same prize pool. In order to gain equity, they must win at a rate that is double what they would win by playing individually, and I don't think this large an advantage is possible.

Thoughts?