Of course you are right. The legs are too short in places (e.g., Ramsey hairpin, Gooseneck etc) to fly effectively. However, I hammer round with max rate turns to smooth out the wrinkles to get my 20 (or so) minutes... The iNavCalc route I posted-up has smoothing compared to actual roads -- but even then, as stated almost impossible to fly.
I have flown round during the actual bike races (very friendly ATC at EGNS that particular day). It is amazing watching the bikes buzz underneath over the mountain...
