Moraghan - I agree in principle with you thoughts about following the "off the shelf RW schedule". However I did just that for Abingdon 08 and went sub 3 with similar PBs to JBFAR.
This year I used the same program again, just tweaked the times down and added between 10 - 30 miles a week and managed to knock 4 minutes of my previous time.
I personally think it a good program, as it works for me, but like you say, JBFAR has an outstanding coaching team behind her that could easily exploit her strengths and work on the weaker areas...
There are also plenty of fast girls at Winchester to help push round the speed sessions....