Brakes are the most critical part and you shouldn't be worried of looking stupid in front of anybody asking most imp life saving question.
I do ask mosssst stupid things and when i hear their answer i feel thank god i asked or else i would have been made stupid.
Dont know about ur LR3, but i had same issue in my old discovery and on the investigation first i doubt brake oil top up, made no difference.
Then air bleed the brake line for removing any air floating in brake oil, still no help.
In end i have to replace the brake booster which translate foot slightest touch on brake pedal x 100 times to stop such huge car.
I suggest you also try in same sequence and see whats wrong. Good luck.