Train Rider relays a report from a suffering commuter on this morning's P508 Worcester train, whose riders got into Boston three hours after they left Worcester:

... Apparently, the MBTA has known for weeks that the P508 train has "flat wheels." Flat wheels can cause the train to de-rail. The maximum "Wear and tear" that's allowed by law is 1 1/2 inches. Some of the wheels on this train had flat spots of OVER three inches. So, they forced everyone off in Framingham and made us switch trains. I got into the office at 10 AM. ...