I want to constantly keep track of the currently selected notes in Live's Clip View, for displaying them on a nslider object. What's the best way to do this?

This is what I came up with, but every time I select a new clip or Cut/Copy/Delete clips, my Undo history gets loaded with "Undo Change". I'm also not sure if having a metro object call a live.path every 30ms is the most CPU efficient solution...