MOT brake test

Hi all, new to the forum so hoping I'm posting in the right place.

Just a quick one on brake testing.

I've had my 53 plate Renault Trafic II (Class 4 2940kg) for 6 years and to date have never had an issue with brakes failing, this MOT however its repeatedly failing on the rear service brakes.

Chatting to the tester today, he said that the combined efficiency needed to be greater than 50% of the vehicles weight which he had set at 2940kg. Its currently 335kgf under, noticabaly on the rear, fronts both locked. Just to add, the handbrake is fine and locked on the N/S.

I've changed the disks and pads as the current ones were slightly pitted and there was a slight fluctuation, handbrake cable was done 6 weeks ago, I've bled the system to eliminate any moisture all with no joy and brakes and handbrake have been adjusted as per Haynes manual.

The fact that it's suddenly having issues this MOT and it's a new garage I've gone to, my question is, should the brake test vehicle weight be the 2940 GVW, should it be based on the presented vehicle weight (which coincidentally the gov. UK site eludes to if I'm reading it right) or is there another weight that should be used for the brake test (ie: off a data sheet)

Just thought I'd ask here before going back tomorrow.

I'm sure there's more info that I could add, please ask if you need any.

Cheers, Wayne