Well, that post and your's does tie in with what I've always found - it doesn't matter what is happening on board the train, so long as the wheels are turning nobody outside that passenger compartment of that train thinks it's a problem. Once the train get's delayed by the guard, however, to deal with ithe problems or wait for BTP to turn up, everybody (including the driver) wants to know why did you dare cause delay minutes and why are they getting home late.
Then again, maybe my view is skewed as I'm not the one having to look at the spotters on a nice sunny afternoon as I whizz past them, but am the one having to get up close and personal with the drunks on a Saturday night while locked inside a moving vehicle with them, knowing that the next three stations are unmanned, the two BTP officers on duty for all of South Wales are a 45 minute drive from the next station (if they are available at all), and that when I eventually get back to my depot, I'm looking at several hours of form-filling, interviews and please explains.
This still doesn't justify Spotters trespassing, but might explain why I'm not as dismissive of troublemaking drunks as somebody who is locked in a driving cab away from them all and carrying no responsibility for them, or tolerating them on their platform for five or ten minutes knowing they will all be getting on a train soon and becoming somebody else's problem.
As a guard myself I fully agree with and share your concerns about being locked in a train with a load of drunks . I wish that there was a crack team of BTP officers on every train I have to work on Friday and Saturday nights.
On the flip side though I still think trespass should be treated relatively seriously . The driver might suspect it is just spotters but you can never be 100% sure .
As much as I dont like being locked in a train with idiots on a Friday and Saturday night . I also wouldn't like to have to get out of that train and walk along the ballast to see if that bang the driver has just brought the train to a grinding halt for is a trespasser that we have hit . Id hate to have to see the effects that would have on the driver if it is . And id hate even more if I would have to be locked on that train with the drunk maniacs in the middle of nowhere for hours because someone has decided to help themselves to the signalling cable .