[The Cheat]

The Broad Street Subway has a kink that routes it around City Hall tower, and the Market-Franford Subway also misses the tower part, since the tower is north of center. The Regional Rail tunnel actually goes under the Masonic Temple, and they had to do some special shoring-up to keep that intact while the dug the tunnel. Continuing east tunnel turns north and runs along the eastern edge of The Pearl, and if you read the architect's comments, you'll see why there's only low-rise stuff above the tunnel.

It seems some people have forgotten the huge concrete pour they did overnight for the foundation of the Comcast Center, or when the walls of the Suburban Station tunnels were visible from the outside when they dug the pit.