What accountability do you want?
Why do steam enthusiasts always seem to think there is a vendetta, hidden agenda and/or conspiracy against them?
Perhaps because it's happened before (BR steam ban post-15 Guinea Special)?
I understand that safety must be the primary consideration. I question, however, the value of route availability ratings if an RA9 loco can be allowed to use an RA6 route. I don't make a big thing of this, because in most cases it's utterly irrelevant, but I do have scientific training in biology/medical research to Masters level, and thus I find the above fact incredible (in the literal sense of the word). If science categorised data with a similar lack of specificity or rigour we'd still think that phlogiston existed.
I also find it odd that NR should give initial approval and then reassess the route a few months later; surely the assessment was planned when the initial approval was given? If they had warned the NNR at that time that the route was to be reassessed and this might result in a late revoking of permission for the A4 to use the line, the railway wouldn't have been left scampering around for a loco in steam to fill the timetable. I infer from this that NR either didn't know the reassessment would happen (proper planning prevents p***-poor performance) or, more likely, they knew about it but "forgot" to notify the NNR.
When one adds this saga surrounding Carlisle, especially if information provided earlier in this thread is accurate (no measurement of platform clearances despite an "assumption" of 25+mm of lateral movement) then it seems bizarre to say the least, and, even if there is no anti-steam bias within NR, it gives the impression of one. I'd have thought that, with PR being so prevalent in all big organisations, someone would have made the point internally that repeatedly disrupting steam movements on the network doesn't give a good impression.
It also worries the NNR, as they previously arranged for
Tornado to visit for one of their Galas only for NR to shut the line from its base, again at the 11th hour. As Trevor Eady (General Manager of the NNR pointed-out on local radio, it gives the railway a bad reputation - while we know it isn't their fault, Joe/Jo Public who want to see a big express engine might reasonably conclude the the NNR are making speculative promises. Such reputational damage can make a huge difference to an organisation whose profits are small enough to be vulnerable to such factors.