Product review (5 stars): I'm pretty sure I probably had 2 grooves on and one ...
This is the second belt I've purchased.  One thing to keep in mind is that on the drive gear there are 3 grooves as well as a gap on either side.  I think my last one wore out so quickly because I didn't properly seat the grooves on the right spot.  I'm pretty sure I probably had 2 grooves on and one hanging off the side after seeing the way the belt was shredding.  Tip to anyone replacing this belt, make sure it's on the right grooves either using your fingers or an angled mirror.