^^^Aside from the repeated use of the term "Frisco" thereby making my teeth grind (
), I don't want to have to reread everything that's been posted to find where you got that 20 units per acre figure, but if it's an average for Mission Bay as a whole, it's not very helpful because a large swath is NOT residential (it's the UC campus, hospitals, research labs, offices, open space--parks--and some retail), hence contains NO "units per acre". I'm sure looking only at the residential parts, it's far more dense than that, being pretty much made up of 5 - 13 (roughly) story apartment and condo buildings (a few buildings like the Avalon apartments and the UC housing are even taller as I recall). You can see a lot of the housing in this photo (the building along the water in the lower right, however, is the China Basin Building discussed above--not residential):
As to the reason why it's not taller still, there are two reasons. Partly it is NIMBYism--tall structures in that area would block a lot of views of the Bay from Potrero Hill and those folks screamed loudly. But mostly, as one article says, the idea for the residential was to create something resembling some existing San Francisco neighborhoods--which rarely contain anything much taller than 6 stories and are mainly 3 stories.
On the other hand, I agree with you about the maliciousness of design by committee and the SF planning process.