From what I've read, the DTCC (www.dtcc.com) have a pretty darn good idea of where all of these are (maybe not down to the granular level of knowing they're in my account or yours, but not TOO far up the food chain from us). They're the ones that usually get the blame for not keeping up with it, and the SEC gets the blame for not clamping down on the DTCC.
Pretty tricky situation... If they stopped it immediately and made all shorts cover all of these FTD's (again, on the assumption that it is as widespread and rampant as it appears to be) it would have a very crippling affect on the entire market. If they just stopped it on CHNW though, I go back to the "retire in Fiji" scenario. ;)
Do watch the presentation though and come to your own conclusions.... I'm just regurgitating from that and a lot of the other things I've read on it recently. I'm opinionated on it, but certainly no expert by ANY stretch of the imagination!
Time for bed, I think… ‘night all!