I don't think I've ever had a less than 45 minute wait to drop off one (1) checked bag when taking Delta from BOS.
Today, the Green Line was empty @ 1pm from Copley to Gov Centa, the Blue Line was empty to Airport station, the Massport shuttle bus was empty también.
And then I entered Terminal A and the bag check line of course had 8,000 people in it.
Delta gets everything else right, why is this one thing unfailingly a pain in the tuchus?