|4 one shot timer signals at Canal St replacing what had once been left to the operator's skill.|
We can see PTC having the same effect with SEPTA, Amtrak and Metro North all having to increase their running times to account for the slower speeds. Speed control thresholds don't take existing safety margins into account and calculated braking curves are also highly conservative making all trains run like they have a grandmother at the controls. All of this will reduce capacity and make making up time a concept of the past.
Some insiders have stated that the true reason behind the slow down of trains using speed control signals is to gain leverage over the unionized workforce in contract negotiations. Not only does removing skill from the position allow for the recruitment of younger or less skilled workers, it also prevents rulebook slowdowns, the Transit Worker's union only weapon since strikes are banned by state law. The idea was to slow the system down proactively so that work actions would lose their power (think of the frog in the boiling pot of water). However now the scuttlebutt is that management simply doesn't know what it's doing and there is no real strategy behind the slowdowns aside from doing what the safety consultants recommend.
An interesting point of comparison is The PATH railroad that runs between New York and Newark. It uses pretty much the same equipment and signaling system, but the timers are timed properly so that the operators can run right at them at the prescribed speed and not get tripped. In fact, before 2010 the PATH equipment didn't even come with speedometers, requiring the engineers to know how fast they were going on instinct.
Anyway it will be interesting to see if the MTA is forced to back down from its position of slowing down the system in the name of "safety" or if they will stay the course and try to extract billions from the government for such Wunderwaffen as CBTC. Which, I should mention, is only expected to deliver an additional 2 tph on the 7 line, resulting in a frequency that is still below historic levels when operators were given the freedom to use their skills to maintain the schedule..