As it stands now FRIENDLY FIRE does a small amount of damage to the teammate who was hit, but it also cancels your attack if you are hit by a friendly, which is not a deterrent for a selfish player on your team who is either trying to steal the kill or is just inexperienced (80% of the players are selfish and oblivious to team play).
I propose a friendly fire strike does damage to the CULPRIT because this would make them think twice about wildly swinging into a teammate's back. The times I've been most frustrated with this game are with connectivity and with my teammates -- very rarely because of an enemy player.
Here is a common occurrence...
I fight an enemy player 1v1 and I have him to about 15 - 20 damage left. I get a GB and... Boom! I'm hit in the back by one of my teammate's attacks. This now cancels what would have been an execution and instead turns it into an opportunity for the enemy to either block (and most likely get revenge) or worse, my teammate follows with another attack and just straight steals the kill from me..
Now not only did he take my kill, but he now also thinks that what he did was an intelligent idea and will continue to do it FOREVER.
This specific mechanic in the gameplay needs to be changed so that friendly fire is an electric fence/shock collar for selfish and quite frankly poor players. It can still cancel MY attack if you think that enriches the gameplay, but I don't like that there is absolutely NO punishment against a player who is...
1) Selfish
2) Frantic
3) A Weasel
4) Oblivious
Please add this to the list of things to consider for future patches.