Thanks for the info mate, good to see two 'practices' working hand in hand there.Done this a fair bit now. Twice in the last week. A fair few rooftops I've put on here are external climbs. Part of the process of this hobby now for me.
Edit: for anyone interested, these were all external climbs...
The Chambers, Manchester
Queensgate Market Hall, Huddersfield
A couple in Keighley
Huddersfield Town Stadium
New Street rooftop, Huddersfield
Industrial Co-Operative Society, Huddersfield
George Hotel, Huddersfield
Contact Theatre and AMC Rooftops, Manchester
Also, Urbis and G-MEX in Manchester... awaiting film to be developed, and I'll stick them up. Naturally, the extent and difficulty varies with each one... I am not a natural climber by any means, I don't go bouldering or anything... but it's given me a new, refreshing outlook on rooftopping in the city... a new challenge... and is certainly more interesting than the 'get past concierge / get in lift/staircase / go out of hatch' approach to rooftopping.