The woodlots wouldn't all need to be razed (there's more than one), but they do help compromise STC's urbanity. You can't just build condos a km away to compensate. This assumes, of course, that anyone actually wants STC to become urban and not just built out. I wouldn't be opposed to some of the woodlots being developed if they're sacrificed to an urban STC (a nice urban boulevard, as wyliepoon mentioned)...I'm not suggesting it so that Tridel can add another notch to its bedpost or so the STC secondary area can reach arbitrary residential density targets.
edit - adma: it's your response that's kneejerk, not my suggestion. Somewhere along the way the woodlot "pads" along Borough Drive reached a point where some of them were developed and some of them weren't and someone said "stop!" and froze what was left of them in place. Unless Moriyama's original plan for the area (if his was the first comprehensive plan) included these specific woodlots (and not just any old woodlots), questioning if more developments should take place is entirely valid. As if my stance is as anti-suburb as 'kill the detached houses and parking lots and save only the trees,' anyway...