Watching a local Toyoko Line train depart Yokohama Station while waiting for an express. Since the line is seamlessly split (at Yokohama Station) between the Toyoko Line and the Minato-Mirai Line, some of the trains are Toyoko Line (surface) trains and some are subway trains.
The only disadvantage to there being two lines instead of one is the cost. You always pay more when going from one line to another than if the entire line was run by one company. On the other hand, when two lines run in parallel, then you tend to get faster and cheaper service, as the lines compete with each other. So different lines in series means you pay more, and different lines in parallel means you pay less.
横浜駅で、東横線の各駅電車の出発 東京 (Recorded on Saturday, March 13th, 2010, at 6:58 p.m.)
Lyle (Hiroshi) Saxon