I agree it's strange: I need 100,000 BA miles to fly in business on BA from YYZ-LHR, but only 60,000 AsiaMiles to fly the same route in the same cabin.

Incidentally, for Canadians out there, the RBC Avion VISA card now allows you to convert RBC reward points to BA, AA or AsiaMiles. This means that you can get a free business ticket on BA YYZ-LHR (using AsiaMiles) after just CAD $60,000 spending.