Trim Solid doesn't seem to work consistantly, wrote a workaround...it there a better way?

Hello,

I am just starting out in Grasshopper and am completely baffled by the tree and sublist things.  But I managed to make a gizmo that works much more consistently than the stock Trim Solid function.

I'm doing a split since that rarely fails and then doing a UV point sample test via PointInBreps.  If you guys have any tips on a better way I love to know, but for now, this seem to be working pretty well if a bit slow.