I missed this from before. This part of the story gives a great insight on the issues with much legislation in City Hall:
"The proposal initially would have applied to buildings of 25,000 square feet, but the threshold was doubled to make sure the city's Office of Sustainability could manage the data, Reynolds Brown said. She did not know how many buildings would be affected. "
They propose legislation (copied from other cities) that has criteria based on what a Department can handle, even though they have no idea how much data it would generate... which also means they couldn't have possibly investigated the impact of the legislation proposed.

Philadelphia set to assign green score' to buildings - Philly.com