Sometimes it works; other times you just have to take whatever the sign is saying on faith. On the inbound platform at Davis, at least, things is weird. Trains are often listed as due in "1 min" for, say, five minutes. Or ten. Sometimes the ETA will change magically before your eyes to "2 min" while you wait, which means either someone or something is trying to adjust for lost time darnit, or that the train is actually rolling backwards now. I cannot discount it; you cannot put anything past the MBTA at this point.
The display board gives you the ETAs for the next two trains coming your way, which you'd guess would put an end to conductors telling a crowded platform the ol' lie "There's another train right behind us", but it doesn't. (Those wily conductors have been known to actually tell the truth from time to time.)
Happily, the display board can also provide thrilling and gripping display-watching drama on par with anything HBO can give you, only without the violence and sex. (The cussing, however, stays in. Hooray!) Last night Sonya and I watched as the Braintree train, which at this point had been due in 1 minute for fifteen, was nearly lapped by the Ashmont train behind it. The Ashmont's minute countdown was actually working, and we began to take bets on whether the Ashmont train would in fact pass the Braintree train in mid-tunnel, which wasn't likely and we weren't expecting it, or if the Braintree train had just given up and never even left in the first place, which was slightly more plausible.
The Braintree train arrived first and we believe the Ashmont train was helpfully pushing it.
So in conclusion, unless you like staring at ads for products no longer meant for your demographic, there ain't much else to look at on them subway platforms.