Jubilee line dwell time survey

TBTC does record the dwell and this is very helpful for timetabling, as where scheduled dwells are too short, trains will tend to stop for longer than planned and gain lateness and this will be apparent in the data. However, TBTC holds all trains to time. This means that the dwell time data will not show where the dwell is longer than required for alighting and boarding to be completed. Outside of disruption, the dwells will not go below the scheduled value.

Manual surveys allow for a comparison to be made between (a sample of) alighting and boarding times and the dwell data. It may be the case that at some locations at some times of day the dwell is insufficient and passengers are being left behind (and have to wait longer than needed) and the headway could accommodate a longer dwell, or there might be others where time is wasted and journeys could be slightly accelerated. The sections between Stanmore and West Hampstead plus North Greenwich and Stratford have scheduled stands denoted by a letter or plus sign in the timetable. These are to even out the headway at termini or accommodate detrainment. Again the TBTC data will not show the time required for passenger boarding or alighting. Impressions from Train Operators will be useful as there is a need to judge whether the conditions are typical, though Oyster 'taps' might also help with this...

I finally remembered to take a photo of the notice:

(click for a larger version)

The 30tph circle seems to indicate an attempt to figure out how many trains could be absorbed at a maximum? Having used Canary Wharf jubilee station since the day it opened (with a limited service to Waterloo I think as the two sections were not joined), it really is an interesting station for somebody to study dwell times and passenger flow in.
In the evening peak, 515pm to 615pm at Canary Wharf, I feel dwell times are increasing due to a change in passenger behaviour. Since about 2006 in the above window, the limiting factor as to when a westbound train leaves is that the train is absolutely full and no one else can board. While the number able to fit on a train hasn't changed (I've put on ten kilos, but that's just me), mobile phones have made a change in my view. People walk onto trains more slowly than they did 15 years ago. I am now over 50 with bad knees caused by lifting heavy weights and early osteoarthritis. Yet, I see people half my age dawdle into trains slower than me at Canary Wharf. Some are easy to see why: they are looking at their phones while boarding (I notice this more at PED stations) while others stop as soon as they take two steps into the train to check their phone.
This effect closes up the gap between trains. I can see that by checking the train indicator board when alighting at Westminster or Green Park to change: the gap between trains shows as smaller than it showed while waiting at Canary Wharf. In the evening peak, whatever gap/frequency line controllers are releasing trains from Stratford and North Greenwich, Canary Wharf dwell times normalise and evenly space out the service.
October this year has seen a few occasions where very aggressive crowd control outside the station has meant trains between 530 and 6pm have left the station with spare capacity, but that is a recent and rare phenomenon (which should also be looked at).
I also find the timing of the survey interesting. Over 20 years I have noticed that the heaviest loadings of the year at Canary Wharf are in October and November, as no one is on holiday. Schools are in session, the ski fields are not open and most Canary Wharfers are just back from a beach holiday, everyone is in the office.

At some point between Saturday evening and this evening the notice has been moved to the front (ie t-op visible) side of the noticeboard. I still don't think that they'll have an easy time reading it - it's not designed for viewing at a distance and is too wordy for the short time they have.