Tun Kai Poh
Hero
I have seen it happen a lot. If the group is cool with secrets, then go about the secret keeping (detailed notes help). But it should be part of your group's social contract and it's worth taking a moment to discuss. The GM taking aside a player can then be a really dramatic and memorable moment.
Amen. Consensual PVP and intrigue can work really well. Everyone just has to be on the same page ahead of time.