4x4 body mount prescribed areas

Hello all,
I test quite a few Landrovers & other 4 x 4 vehicles, which as I am sure you all know get pretty rusty. I have previously had a trade customers, customer come in to tell me that he had been to two other seperate garages, one who was an mot garage , who had advised him that the vehicle should never of passed an mot, because it had corrosion on the body mount areas.
I have just carried out a test on a Discovery, which was tested locally approximately two weeks ago & had been failed on body mount prescribed areas, which in my opinion should not have been failed. 
I used to fail vehicles for excessive corrosion in body mount prescribed areas, until I went on my first refresher course, where they pointed out that there needs to be a cumulative amount of corrosion to make the body insecure.
I suppose it's up to the testers' personal opinion of what insecurity of the body was, but it would have to be quite bad in my opinion.
I think it would be a good idea for Vosa to send out messages or special notices to clarify situations like this & would be interested what others on here think.
Kind regards, Andrew