My understanding is that the NRM operated Flying Scotsman on the Scarborough line both with and without smoke deflectors after buying it - but before withdrawing it for its current overhaul. The results of these trials confirmed the wisdom of P Townsend in fitting the German design of smoke deflectors and a report of the NRM trials was confirmed by the NRM shortly after withdrawal from service. I am not saying that the cost of running in various forms was the reason for the bankruptcies of the various owners but only Pete Waterman had the savvy to understand that running costs include financing the next overhaul of the loco. It is at that point decisions can be made asto to what appearance ( shape ) the loco will carry because once made, any changes will add to the overhaul cost. Whilst agreeing that Pegler lost money because his USA tours didn't generate the (British ) support required to make the American trip successful both Pegler and Marchington under-estimated the cost of the overhaul thus depleting their already reduced finances and over-estimated the income they would make to fund the next overhaul once it returned to the main line. I believe that Pete Waterman fully costed his involvement with 4472 and charged the "proper" hiring rate despite protests from "enthusiasts" that as a millionaire he should subsidise 4472 by charging rates that "enthusiasts" could afford rather than rates that 4472 needed to be financially secure. Once Pete Waterman calculated that 4472 was going to become a bottomless pit ( i.e earn a lot less than was needed to maintain its running costs let alone finance the next overhaul ) he made the astutely correct decision to sell it on before he too became bankrupt. And that brings us back to the basic point. Flying Scotsman needs to earn money to fund its operation and overhauls; at £1 million + they don't come cheap thus someone has to pay and the NRM as its current owner has to fund that. The fact that enthusiasts over-subscribed the initial appeal simply gives the NRM a once-off chance to fund a proper and rigorous full overhaul. It doesn't matter what Flying Scotsman did in the past, its future operation on the increasingly regulated main line means that any decision will be made on the most economical way of operating designed to raise maximum revenue to both fund its operating costs and future overhaul. It is therefore best left to those responsible for operating the locomotive to make their decisions whilst less knowledgeable enthusiasts should accept their wisdom and savour the sights and sounds of locomotives at work rather than beggar the questions that are not theirs to either ask or answer.