Old Fella, my comments were to Shell Management.It would be interesting to see what information and experience he bases his comments on.
I'm a current FE on a Lockheed C121/Connie so I have some experience in running 4 X R3350s on lower octane fuel. Our operation has so far not had any dire problems with either our 1049 or Neptunes with power recovery turbines.We also don't use high blower.Biggest problem and the only reason for any engine shutdowns for us has been fouled plugs. Two fouled on one cylinder is a mandatory shutdown. Both the Neptune and L1049 are fitted with an engine analyser so all 36 plug conditions are readily observed.
The trick with these engines seems to be to follow the procedures exactly and never allow them to be negatively torqued, landings being the exception.
On the Neptunes including both recent accident aircraft (from the photos) except for low fuel, there is always the emergency option of using the jets to get you out of trouble.
I do agree that the Neptune with propjets would be an interesting fire bomber.Probably a bit lighter as well because it would allow the removal of the jets.
It is interesting that the Canadians are moving to Electras and CV 580 propjets as the US is going British jets.
Wunwing