stevie you could argue that on any modification on a cars testable componants, be it ap 6 pots, gaz coilovers etc which carry no type approval.......

but that would be irrational and IMO same with a handbrake cable. 1 clamp would probably be strong enough... 3 should be overkill and the odds should pale into insignificance. you could argue that ap 6 pots might leak..... or suspension might collapse on a pothole.