ORAC,
Mostly right, but the reasons for this were interesting (to say the least). Using the wing sweep (auto or manual), which one has/had to, would take the aircraft through an astonishing number of defined limitations (speed, normal g, aoa and rolling limits). The aircraft could only record consumed FI at set points and (we all know) the computer(s) didn't have the capacity to interpolate between these points. In truth, no one really knew what happened anyway, because the testing on the fatigue model was still running (obviously).
The apparent fatigue consumption as recorded by the fatigue meter didn't match what was really happeneing (as we discovered when they opened them up for the first time) AND the assumptions about how the F would burn FI compared to the GR were based on a fictitious interceptor role; we then went on to do loads of low level and a lot of 'high' g manouvring that wasn't 'expected'.
As far as I know, there was no significant FI penalty in moving the wings under normal g - there would have been yet another set of endless NO and NE limits for that if there were.
The issue with AWSMDS wasn't one of fatigue. It was, I am convinced, to do with clearances and money.
IMHO.
Courtney