Engines, thank you for making the very point I made concerning the B-model not being the ideal solution for the RAF. I agree, if the UK wanted to go down the JSF route (and there weren't so many other options at the time that would be gen 5 and with a lifespan projecting far enough forward) they should have selected B for Navy and A or C for the RAF. When it came down to just one model for both, B it was. And, yes, that was pretty much how the RAF 'selected' the B.
As an aside, I still think the C would have been a better choice for both, with the appropriate carrier, but the RN and USN clearly have different views about projecting air power.