The talk on the forum inspired me to have a go at this on Sunday. I completed the route solo unsupported from Ambleside going clockwise, ie High Raise, Scafell Pike, Great Gable, Grasmoor, Skiddaw, Helvellyn, High Street. I measured the route on my Garmin apart from the first 3 and a half hours which I measured on the map. I make it 64.5 miles, so just 1 mile shorter than my measuring of the BG but 18000 feet as opposed to 27000. I finished in 17 hours 45 mins. Its excellent training for the UTMB which was my purpose. Long climbs and descents interspersed with long flat bits which I'm not very good at.
Reminded me of how tough the UTMB will be - makes me quite apprehensive!