Since it's been brought up, my 61mm SC Pulley sheared into three pieces a couple of weeks ago; I'm not sure if it was mine that you saw the pictures of though as I sent it to some local forum members but didn't post it anywhere myself. I believe that excessive heating of the aluminum pulley caused points to get weaker overtime and eventually lead it to shear when it was under stress; the air injection tubes managed to keep the pulley from going rouge and don't appear to be damaged other than minor scraping. I have reached out to EC and they had no issue replacing it with a 65mm SC Pulley, I'm satisfied with that offer, I will be stacking pullies at a later date.

I noticed that there were other spots that appear to have weakened on my pulley other than the points where it sheared, if you'd like to check yours for structural stability then I'd suggest removing the pulley (or belt) and checking the groves for what looks like hairline fractures or cracks.

i.imgur.com/zQFSekl.jpg
i.imgur.com/23YWEVJ.jpg
i.imgur.com/sYtUk84.jpg
i.imgur.com/F2jSkQX.jpg

Sorry that I didn't post about this here when it happened, I should have.

Edit: I waited quite a while to put the pulley on after I purchased it, I think I've been running the pulley since early 2013.