Question about Football "Suicide" Pools

[dr.strangelove]

I usually run a basic Superbowl Pool at my office (the traditional 100 boxes on a 10x10 grid style pool). This year several people have asked me to run an NFL suicide pool. I've never been in one of these, but have heard of them.

My understanding is that each week a person picks one team to win straight up (meaning no spread or points used to determine a winner). If the team picked wins, the player can continue in the pool the next week. If the team picked losses or ties, the player is out. A player can only pick a team once during the whole season. If a player mistakenly pick a team twice, that player is eliminated.

Are there any other rules I don't know about?