[M. Incandenza]

De Blasio's clearly pro-development - he's made it clear that easing the housing supply shortfall is the best way to create more affordable housing. My best guess is that he just wants to get as much guaranteed affordable housing out of this project to set a baseline for similar negotiations going forward, and to demonstrate to his supporters (who are not necessarily responsive to the supply/demand argument) that he's fighting for affordable housing. I'd be very surprised, though, if he actually allowed the project to get spiked.