Grading system = Rider Control.
Didn't work in the past and caused problems without the threat of the EU. One challenge through EU courts and speedway in deep sh*t. Riders now are just scared to as they will be effectively blacklisted.
Unless all the riders contracts are held centrally, ie all owned by the BSPA or SCB, then effectively the rider control system is a restraint of trade.
If the clowns at the BSPA don't get their house in order soo, then the relevant authorities will have to force them. Not good for the sport at all.