Or when traffic re-routes, a major ISP will temporarily congest its own intra-AS city-to-city links on a few key paths, for their own router-to-router interfaces.
So no, two cuts like this are not something out of ordinary. The fact Comcast is cheap and don't have redundant pipes/contracts to operate secondary backup lines is simply being cheap and saving money on their part.
the more cynical side of me says that an intentionally crashed truck looks the same to outsiders as one that was crashed to cut the fiber line.
but i really don't think it's the case that there is foul play here today. this is where calculating p values comes in handy though.