The reason: at Battery Park City, each parcel was developed separately. (I'd add that the park space came first, not in the second phase, as with the Atlantic Yards plan.)
Of course, the UNITY plan for the Metropolitan Transportation Authority's Vanderbilt Yard--the key public land within the Atlantic Yards footprint--would do just that, but Thompson has never acknowledged it.
Pros and cons
The Observer's Eliot Brown weighs the pros and cons:
Giving a big site to a single developer all at once—such as the 22-acre, $4.9 billion Atlantic Yards project—could bring a higher bid given, among other reasons, that the developer would benefit from economies of scale and increased values as it fills out the site. But, as has been seen in these strained times, these projects are also quite prone to failure or renegotiation as the developers struggle to get off the ground amid the cyclical economy.
While one site per development could bring a higher bid, in the case of the Metropolitan Transportation Authority's Vanderbilt Yard, the initial cash bid from Forest City Ratner was well below both the bid from rival Extell, which itself was well below the appraised value.
The MTA, under political pressure, agreed to negotiate only with Forest City Ratner. And--as hinted by Brown--this June the MTA, under political pressure, agreed to renegotiate the deal on terms more favorable to the developer.