I didn't see an abrupt change in fuel prices in GW#4, increasing trends were all very noticeable and predictable, so one just needs to adapt and be prepared. Example: I operate DC9s in GW#4, not very fuel efficient, and now I'm undergoing a change in fleet type, pushed by the high fuel price trend. This change was obviously planned according to this increasing trend, it was frankly easy to spot. If my competitors didn't do this, that's their problem, and that is why this is a game, some win and some loose. One cannot always win.