Hold short cat 2 rwy-set brakes.Hold short intersection-set brakes.Hold short single rwy in use-set brakes.So why would u NOT set brakes when u asked to hold for take off...???!! Daft...
Consider this...cat 2 conditions,night take off,enter line up clearance given but hold for take off,due seperation. You mean u're gonna trust ANYBODY to hold those brakes with his/her size tens for those critical minutes,with little/no visual reference..??? Not me...
Same when asked to hold for take off in heavy rain with poor vis,ESPECIALLY at night. You've GOT TO BE KIDDING!!
Next u'll prolly be asking pilots to stop using autobrakes cause mebbe they could malfunction and cause a runway blockage...