Thanks for the insights. Having been an observer of construction sites for decades and having a general sense of the workflows (including abandonment of projects), this one was truly baffling to me. The vertical progress had clearly begun and then paused, with no crane being installed when it seemed to call for one; yet, the site at ground/subterranean levels continued to clearly be staffed / being worked. It was so odd to see activity, yet entirely limited to the garage levels.
But as I think about this more deeply, this isn't the first time MITIMCo has done something like this; it just wasn't as dramatic in the other case since there was no garage. That other case was the One65 Main residential tower. They built part of the ground level and started the core (with rebar poking up, etc), then paused for a year IIRC before the tower frame was begun. In that case, part of the ground level was shared with the Brothers' supermarket, which opened far in advance of the tower. Normally construction pauses scare me, but MIT/MITIMCo is a rare case of greater confidence, given the prime location of this parcel, the high interest rates slated to come down soon, and the fact that MIT clearly will not want a part-built rusty steel frame sitting in front of the Sloan School for an extended period. They always have the option to build it out for institutional use if they can't find a tenant, yet if rates become more favorable.