Not all these things were created equal. June and September event rumors, as they related to a nMP, were weak at best. And it would be fairly unlike Apple to do two events less than a month apart, making a Nov event a remote possibility. Its October or the can gets kicked into at least the first couple months of 2017. At which point, yes, of course that's no certainty either.
This is all getting stuck in the weeds though. E5-1600 v4s have really only made it into people's hands as of about a month ago. At that point the October Mac event was fairly certain, but if a Mac Pro comes out of it is still anyone's guess. However, considering the cost of switching from Mac to PC in a professional environment, at least for many, a month wait just to see if a Mac Pro will be an option isn't a whole lot to ask. If you were limping a long and things really sucked, then chances are you didn't have the choice to wait for Broadwell E5-1600s or the Mac Pro.
Anyway, this topic has become boring. You've said your piece, I've said mine. We get it, the nMP sucks compared to modern equipment. For the price and depending on workflows, that was even true the moment it launched. We didn't need broadwell or GTX1080s to prove that the nMP, well, kinda sucks.