It looks silly as hell, but since Rock Paper Scissors is basically rolling a d3 it would actually make a nice FATE conversion... win means +1, tie means 0, lose means -1. I am thoroughly opposed to larps in general, but they'd be at least a BIT better if they didn't use those fucked up Mind's Eye Theater rules.

It doesnt have to be silly...
It can be done descriptively call them Direct, Guided and Deceptive or Simple, Aimed and Fake if you wil, then add in some Risk choices to control how much oomph you are throwing in to it... and you have something with flavor. (my risk plus your risk equals the bonus to the intensity of the result for both of us)

Note while larping you could use cards with the words on them to ease simultaneous revealment.