When the MTA announced in 2010 that it would start issuing notes to delayed passengers to prove the train made them late, it sounded like the go-to excuse for school or workplace tardiness might end. But the system has a problem with tardiness itself, sometimes offering said notes weeks after they might have been useful. As the New York Times found, the notes basically wind up coming in handy when you need an official excuse, such as in a workplace where a record of lateness can lead to discipline. But they won’t help you if you miss an important meeting, or get sentenced to detention the same day you were late — nor will you be expected to obtain one. In those cases, the “subway traffic” excuse is just as flimsy as ever.