In reply to Milesy:
So here's the tick list:
Curving Crack (The Whangie)
Punk Rock (Neilston Quarry)
Pulpit Crack (Loudoun Hill)
Cave Crack (Loudoun Hill)
Dee's Crack (Loudoun Hill)
Promontory Direct (Auchinstarry)
Orange Flash (Auchinstarry)
Lion (Auchinstarry)
Walk on the Wild Side (Auchinstarry)
Easy Contract (Cambusbarron West)
Sunsetter (Limekilns)
Forbidden Colours (Limekilns)
D-Day (Limekilns)
The Waullie (Rosyth Quarry)
Broken Pillar (Rosyth Quarry)
Shoskred (original LH line) (Ratho)
Between Contracts (Ratho)
Cracking Up (Ratho)
Ourobourus (Ratho)
Gaucho (Hawkcraig)
The Shield (Traprain Law)
Piglet (Traprain Law)
Burp (Traprain Law)
Any more contenders? What about Craigmore Corner, Windjammer or Stonefall Crack (not done any of them myself)?
I've not included Dunkeld as it's not in the Central Belt by any reasonable definition!