The figures quoted are VOSA`s figures so unless VOSA are not doing their QC job properly these are all justified & genuine fails. The question should be, why is the rest of the EU so lax.
As for the accident rates through mechanical defect I remember from a previous meeting there are "Hotspot" countries with a higher incidence than others,I believe the UK being the lowest.So some standardization and overall inspecting authority is obviously needed. My suggestion would be the rest of EU goes to 3-1-1 and VOSA becomes the inspecting authority.
However, after Gordon s trouncing in the elections he may well be prepared to throw us to the lions whilst crying that he "feels our pain".
Below are the figures in %. No numbers are given as to the amount of tests nationwide and these figure relate to class 3/4/7 only. There is a slight anomaly in that class seven requires additional tyre checks and this may influence the figure for that CG.

Component Group Scheme Average UK 01/2008
Lights & Signalling 18.40
Steering 3.62
Suspension 11.07
Brakes 12.02
Tyres 8.53
Road Wheels 1.76
Seat 3.09
Body & structure 3.02
Fuel & Emissions 6.80
Drivers View of road 7.70
Registration Plates 2.74

What is interesting is our average tests per day is 12.50 and the VTS Scheme is 2.27 !!! so ours always flags as abnormal anyone else get that?
And in answer to the original question,yes we should be allowed to carry out repairs.