It'll take a brave man to try that out !!!
Not sure, but i think the Q5 handbrake is hydraulic ??? You can feel the brake pedal move when you apply / release the parking brake so i guess it's not a cable system. Also, If you stand by the car while someone releases the brake, you can hear the brake release.
At least it should stop me getting charged for a "sticky brake cable", twice (both sides from Lexus), down the line some time
had the same thing on my RRS - for the RRS once its been used at speed (i.e. in extreme circumstances), then the car has to be checked by the dealer as it stresses all the braking components to their limits
Tried it on a customers carpark yesterday that was sheet ice. Whilst driving with accelerator pressed a quick message flashes up in the display that park brake has engaged, quickly goes off and car does'nt brake. Without pressing the accelerator its the same as jamming on the brakes.