I did a bit of firing many years ago.
This stopped pretty abruptly when it soon became clear the average steam crew is a bit 'what ever' in their approach to timetables, customers and completing everything they need to.
Oh and the moment when the handle of the firing shovel came off, resulting in the metal and shaft flying into the rear of the fire box and me then having to hand bawl coal into an 8F for an hour!......this was followed by the comment from the crew, oh you don't want that shovel its got a dodgy handle, been like that for years (arseholes!)
Yes, nothing I've seen on the Watercress line has made me want that job, especially in the weather we've had recently.
I have seen all sorts
Black 5 with drain cock issues, rather than take it off they bunged a 9F on the back of the train and pushed, buffers of the rear coach nearly overrode the next carriage and not surprisingly, the cylinders on the black 5 were damaged. (Llangollen)
On ours they ran out of coal because they forgot to check prior to leaving, que stopping every mile to pick up any random bit of wood, sleeper, fence, road kill they could find to lob in the fire box.
Another where they were heading up the bank at Llangollen and through the tunnel and ran out of steam so had to roll back, all because they failed to get the boiler full and simmering well before setting off so lobbed water in half way......which cooled the boiler.....and they also had a small vac leak on the coaches (only did a basic brake test) and could not overcome it due to lack of steam!
Dropping the fire because the injector was being a bit temperamental.....but doing so as the first action long before there was a real danger and then fixing the fault within 5 minutes.
Always being late onto the train, preferring to sit on shed drinking tea rather than coupling up and getting heat into the coaches.
Just piss operating in reality, heritage railways seem to attract those who have failed in their main job!