As for the record 'carrying passengers' how do you define passengers? Presumably there were railway staff on board the mk4 rake used when 91110 got the record, just as there were in the speed-recording coach behind Mallard. So what difference does it make given that nobody even seems to know whether fare-paying passengers have even done 140mph on the ECML?
It's a point that's piqued my interest before, too: Presumably the differentiation is between members of railway staff employed in some practical capacity as part of the run and impartial observers, although I am not sure why there is such a high level of distinction between the two, given that any passengers carried by these sorts of record breaking runs, including the 154mph run with 91031, are generally invited members of the press rather than everyday passengers.
It does strike me as unusual that the RHDAB have seen fit to designate an entire locomotive based solely on a vinyl wrap that it carries: With space for preserved exhibits being finite - around the country, not just within the NRM - I would have thought that it would have been sufficient to save a virtual copy of the final designs for the vinyl wrap, in a suitable file format that is likely to allow long term access, and any intellectual rights to the design that there might be. You make a good argument that, if we are to have two designated class 91s, better for it to be 91110 and 91131.
It is a shame, however, that we did not have a Railway Heritage Board around to save the WW1 memorial locomotives of the London North Western and Great Central Railways, the locos named "Patriot" and "Valour" respectively: Both examples of loco classes no longer extant.
