It's definitely a better end product to have it buffered/flex posted in the roadway for the sake of continuity and ease of use, but on the flip side, I know of no engineering standards related to the pitch of a bike lane, and the driveway isn't a driveway, it's actually a carriage road owned by DCR.Putting a bike lane on the MOS driveway was evaluated, and discarded:
(1) The grades are too steep to meet engineering standards
(2) The MOS doesn't want it there
(3) It doesn't go the full length of Charles River Dam Road
One of the big reasons why this won't effect vehicular traffic throughput is because it doesn't change the capacity (number of lanes) at any of the intersections. It just takes a lane in between. There is less queuing capacity in the general vicinity, but the same number of cars are making it through the intersections.