Like the old joke about [name of college you pick on here] and their new triple threat offense - it sounds like a great idea to add that new play to the two they had before...
I have done a little of what might be called triple stops. When trying to play along with guitars using the chords I will sometimes play bar chords on the lowest three pitched strings and I play 3 forms (root on each string). I usually pick the form based on a combination of what chords I am between and how it sounds. Sometimes I find it sounds good to switch between forms when we stay on a chord for a while. This is rhythm, but the forms I use are usually picked for a melodic feel (and to keep up). But like Bill, I go medieval on those guitarists a lot. I love double stops!
"First you master your instrument, then you master the music, then you forget about all that ... and just play"
Charlie "Bird" Parker