Thank you DebW and ny biker - that worked!! I was pretty conservative in how much change I made but took the bike out for a short spin afterwards and it's sooooo much better. I'll be riding about 30km tomorrow, which should be a good test.
I don't know why it didn't occur to me to ask the fitters if this was possible. It's not mentioned in Speedplay's leaflet in the box with the pedals, but surely the fitters should have thought to check?!! 
Never mind - TE to the rescue again!!!!
Rebecca
Riley - custom 2014 Enigma Etape
Bridget - 2010 Surly Cross Check
Lorelei - 1979 Puch Princess mixte
Astrid - 2014 Viking Bromley singlespeed mixte
Lucy - bespoke 2012 Brompton S1L
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