It is not being overlooked willfully.
A lot can happen in a day (or two) in terms of branches entering the structure gauge for the route. On a wet or windy day, a part of the surrounding vegetation could temporarily be in a position to strike a train exceeding it's loading gauge. That would be a rare chance event, but nobody here has confirmed that it wasn't the case.
You also haven't read the last line of my post that you quoted.
The report states quite straightforwardly it wasn't windy and the tree had been in that fallen position for 2 years.
Network Rail define this much better than any of us. If it's less than a certain amount the familiar red/white quartered plate is installed. Less again and window bars are required for any stock - there was a longstanding one in Cumbria.
Clearances between trains and structures can be very small, subject to calculations that they won't actually touch, considering things like the worst case swaying of the train and the tendency of the track to move around over time. However the traditional recommended clearances do include an extra area at window level for lines where trains have droplights.
So with hundreds of alert GWR drivers passing this point, most of them in daylight, nobody in the TOC's organisation noticed it?
It look like you are including yourself as one of the 'informed' posters, but there are other comments by informed posters disagreeing with you. The fact is the very little health and safety matters now are now swept under the carpet of 'grandfather rights' and quite right too. For too many years large organisations spouted the 'well it's always been this way' defence. The railway might be one of the oldest transport systems in the UK but it is respected as one of the safest thanks to the process of fully investigating accidents. The role of the inspectors is not to blame but to identify what went wrong and what needs to be changed to prevent a recurrence. In this instance, the recognition of the totally inadequate safety of droplights on main line trains as the primary cause of this event is evidence that it was an accident waiting to happen. That was the same basic reason for the last similar incident so who knows, there might be another one soon. It is an endightment of the railway's commercial imperative compromising safety that their assertion of the impending withdrawl of these 40 year-old trains 'soon'* allows the TOC to do anything about the root cause.
In other words there is no need to make a recommendation to Network Rail to improve their vegetation management because they have already taken steps to do just that
That is true in Central Europe, but vanishingly rare in Western Europe, and I doubt if any has been built in the last 40 years (there's the "photo windows" on some new Rhaetische Bahn trains in Switzerland, but I doubt they exceed 50mph.)
I wonder, have they :
So the RAIB should skew it's investigation findings to apply pressure on NR so that they have to change their procedures which might also help with the annual leaf-fall problems. If they were to do anything like you suggest in an investigation about a fatal injury that was primarily caused by a droplight window that it was possible to lean out of, that would surely destroy the RAIB's credibility faster than the FAA did theirs in the 737 MAX debacle.
