Please move down inside the train

And of course most drivers don’t really care about what’s going on behind them, as long as it doesn’t affect them - eg handles being pulled etc.

Will it not be the case that the Line Controllers can remotely trigger announcements on the S stock? I thought that they were able to do that for service status updates, so it wouldn't be impossible for them to get the train to play "please move down" messages.

And we don't need, or want, yet MORE announcements!

Surely the announcements need to be on station platforms, before train arrival. Dstock's comment "I would think that S Stock ARE fitted with a capacity sensor... This information would available via TrackerNet and used by Line Controllers etc. once the ATC is commissioned." suggests that software could automate an appropriate announcement.

As far as I'm aware the information the Line Controllers get is the loading of the entire train rather than individual cars but even if it was the cars I suspect the Control Rooms have enough to do without checking on individual trains to see if the loading is uneven.

For signalling, a different approach to "carriage passing" measurement is gaining popularity as an alternative to axle counters, namely rail stress gauges, which are simply stuck on to the load rails to see the bend with passing axles. I'm sure that these low-price parts should be able to discern carriage loading with a little software analysis. They could be fitted just after the station "exit" to provide info along the line. Maybe they're already being adopted for the new signalling systems?

I have no idea what instrumentation or data streams is installed on S7/S8 rolling stock. But it might be worth mentioning that the somewhat similar style class 700 stock on Thameslink services already has automated coach by coach loading displays INSIDE these often 12 coach trains. Given the very long distances involved I suspect this is a sensible solution as if people see the display shows loads of space elsewhere in the train they may well use the interconnected carriages to relocate to less crowded areas whilst on the move.

Uneven loadings on the Tube is a different problem, which really needs a different solution, as currently, apart from the S7/S8 stock, people are basically trapped in whatever coach they first board, hence the value of loading information could be quite significant to passengers on the deep tube lines especially at peak times.

Others have already correctly observed how very few people actually make any response to typical please move on down inside the cars type advice. Indeed years of tube commuting has somewhat confirmed my personal view that most regulars have very fixed patterns and no amount of "General encouragement" will get them to abandon their commuting approach. In short what you are trying to overcome, is the entrenched behaviour which leads to "I intend to stand right by the first door on the third carriage come what may as it is where I need to be for my exit" behaviour. This sort of behaviour is probably why uneven loadings often occur on the tube.

IF people really want to tackle this problem then the fix needs pertinent information to be provided to passengers waiting the platform BEFORE a train approaches.

Whilst people ignore most tannoy announcements IF there was some sort of automated system operating which can accurately provide passengers in advance with clear loading information on the approaching train then people (including the regulars) will soon start to pay close attention especially if it gives them a chance of a seat.

So passengers waiting for a Northbound Northern line train at Charing Cross really would appreciate (even if not being happy to hear) an automated announcement telling them the next train is virtually full but there was some space in the first three cars and also the last car. Inevitably commuters may be mistrustful to start with, but if such predictions were consistently borne out, people will quickly figure out where to move to and over time trains will see far more consistent loadings.

Just my 2p

Problem with this is, if you could let people know, when should you do so?

Health & safety should preclude people milling about platforms before the train enters in order to be lined up for the carriage with most seats.

Doing it once the train's in will obstruct detraining passengers in the resultant melee and will send dwell times through the roof.

Announcing it once the train's away not too clever, either, especially if none of the migratory crowd are strap-hanging at the moment the train takes a sharp bend & they injure themselves in a fall. Whose responsibility?

The problem described by norbitonflyer is another matter and another good reason for guards on trains.