Google Maps and Metro: So Close, and Yet, so Far

Google Maps
now has a feature that allows you to specify whether you want driving
directions, or for public transportation.

This sounds great, but if you ask for
directions
from the College Park Metro station to the Metro Center Metro station,
it says to walk a mile and a half to the Riverdale MARC station (what?
Not the College Park MARC station?), take that train down to Union
Station, and walk another mile to Metro Station.

So all in all, just a wee bit pointless.