How odd - I took my initial Class 1 in 2006, declaring mild asthma and use of a ventalin if required, but they pretty much swept past that without requiring me to undertake any tests or the like...
My thoughts exactly, I too never heard of anyone being asked to do an exercise spirometric test on the basis of a history of asthma! My FPV1 dropped 14.7% between resting and exercise. A drop <10% is required for class 1 privileges, and with a little exercise preparation and a costly CAA consultancy fee I was able to improve this and actually improved FPV1 after exercise. It is nothing to worry about but caught me out unprepared!