What's your policy on two players playing from the same IP address?
Some places (e.g. Seals) are OK with it, most places ban it in the client.
I don't want to get into trouble if it's the case that your policy prohibits it but your software allows it...
We allow it, no worries. I don't know what your wife's policy is though, if you win a lot of bitcoins from her maybe you could get into trouble that way.
Since collusion isn't possible playing Heads-Up, there's no harm that can be done, so we leave it open for friends and roommates and husbands/wives etc. to play against each other.