Returning to the subject; I forgot earlier that sometimes drivers are changed on through trains - there is a very small driver depot at Epsom ( unless that's changed recently? ).
Drivers and indeed conductors do change trains there. You are correct that there is a small drivers' depot, for Southern only.
I'm not sure but think this incident may have been a southern doo train. There's a relevant time train shown on RTT terminating at Epsom before being delayed going into the sidings.
I wonder what the set up for doo drivers at Epsom at that time of night is when the train has to be walked through to be checked and cleared before going empties? Are there still station staff at Epsom at midnight and are they required to check train?
Something else aslef and rmt should be checking out???
Yes, Epsom station should always have staff available from first to last train, as they are required for dispatch of all trains on certain platforms, and they do also check and lock out trains for ECS moves. Bizarrely, the SWT dispatch policy does not ever seem to require them, even though visibility still isn't ideal with guards, and it's a pretty busy station.
It is horrible that a driver was assaulted and there is no excuse for someone doing that, but there are plenty of locals who need careful handling and it is unlikely that the driver was simply sitting in their cab if a drunk person managed to pull them from the train (they'd have to negotiate the cab doors, which can be tricky enough to open when you're sober on the older 377s or 455s). Therefore, though I don't know the full picture, I suggest perhaps it could have been the case that the driver was trying to empty out the train or deal with an incident by themselves. It's a sad reflection of society, but if this was the case, it's another reason why I wish they wouldn't, unless at the few unstaffed stations where they do need to lock out a train on their own.
It's always better to have someone else to turn to, to diffuse the situation or call for assistance. In addition, a driver who just wants to speed things up and get home promptly is unlikely to feel particularly sympathetic to passengers who've overslept or overstayed their welcome, and I have seen this cause a considerable backlash at times. Being asked to snap out of "driving" (or sometimes "guard") mode and deal with chucking out drunk people is something which I have seen a number of crew make a bit of a mess of doing over the last few years, as the two sets of circumstances do need very different skills. It's unfortunate that people aren't reasonable, but that's what happens when you mix the poor morale and unpopular uniform of Britain's least-liked rail operator, and the chaos of weekend revellers who are more than a bit tired and emotional. In none of this am I blaming the driver, just a combination of unfortunate custom and practice, which has conspired against them in the worst of ways.