Noah Bierman of the Globe had an interesting piece in Sunday’s Globe on commuter rail’s on-time performance. He found that peak service trains fared significantly worse than non-peak service trains for on-time service.
The interesting part is that that the commuter rail operator, MBCR, is evaluated and reports on the basis of trains delayed, not passengers. What this means is that the bulk of commuter rail riders (i.e. rush hour passengers) experience a far higher level of late trains than the publicly reported data would suggest.
I would suggest that a more customer-oriented metric would be based on the total delay per passenger but that would take a level of detail and information the MBTA cannot currently collect.