Can you solve this deceptively simple riddle?

[Radbot42]

The rules state the group has five minutes to discuss to set their strategy, so during that five minutes the group chooses which color represents odd.

However, I have a much simpler answer. They are only able to use the words black and white, but there is no limit to how many times you can say the word. So the guy in the back who can see everyone's hat, just calls out each person's hat color sequentially, followed by a guess of his own hat color. Guaranteed 9 out of 10 get it right because you *told* them their hat color, and a 50% chance of 10 out of 10.

They are only allowed to say black or white though. It never says when they discuss that they can say anything other than black or white.

[himself]

I didn't get it but I like the solution.