For the benefit of people who are trying to determine the real value proposition of GPUs. Perhaps you have not experienced it but it regularly (perhaps 30% of the time) occurs on flights ex-LHR to SFO. The non-stops are often more expensive than the flights via LAX, whichever day you search. When you put W fare class minimum in, then broadly all the flights are similarly priced. Usually there's no R availability at all. If there is R availability it will be on only one of the days, usually through LAX. And it will be that one flight which will price at £100-200 more than any of the others in W. Take the W class out of the equation and they all price similarly in S or whatever.