I'm not sure NOCs are really much of a factor when it comes to PTs being sent out. Without getting too much into the specifics, my NOC is, well, not exactly one that lends itself too well to immigration, and yet I received not only a PT almost as soon as my profile was made, but a pretty quick nomination from Ontario as well.
Or maybe they just happened to want people from my NOC as well, and presumably not many people from my NOC even consider migrating in the first place, so the pool of competitors for me was pretty small. I don't know.