I suppose MOT testers see a fair few Golfs - the rear discs on my Lancia should have shields - mine looked okay under 20 yrs of muck and brake dust, so I had them blasted and powdercoated in with a load of other stuff . . . they came back lovely and black . . . and lacey . . . they would have looked good suitably shaped and providing support to a lovely lady . .
So I left them off. I know others have failed inspections with holey ones fitted - but I reckon if they had took them off beforehand, the tester would have been none the wiser.
The ones on the rear of my 306 were rotten so I removed them & it has went through several MOT's since with no issue! Better off without them anyway, they cause the inside of the discs to corrode.