Thanks for all your comments so far guys, hopefully someone can supply me a reference to a definitive answer.
It is funny how everyone I have spoken to, bar the guy I'm having a dispute with say that 100ft is way too much and should be sorted.
He is an old guy with no common sense. He taxiied on some rough pitted grass off of a disused runway for parking at our airfield after I had warned him that the grass was not fit for taxi 2 weeks previous. He continued to be pig headed and said that he "will not be told what is what by those with lower hours than him!" . . . . Consequently he carried on taxiing on this grass to park rather than pull up in front of parking space and push back and dropped nose wheel in a hole and which ended in prop hitting mud and stones and engine had to be stopped.
It was witnessed by instructors and by myself and another group member. He washed off mud with a hose and put aircraft back. When confronted he said that the prop did not need to be checked and the engine was not shock loaded as the engine didn't stop on it's own accord, he stopped it himself!!
He did not see it necessary to get check out by engineers even though massive chunks out of end of prop due to hitting a burried rock in the mud, in his words he has flown her with a more "damaged prop" and it was fine and elected to fly a couple of circuits to prove it was ok.
We locked horns on this point as I am in no position to take his word, not an engineer to say that she is fit to fly putting the safety of myself, passengers, public and our aircraft in his unqualified hands!!
The prop / engine apparently was then sent in to be tested by him and prop was merely dressed, now 3 months later in the C of A / annual thuis prop was replaced after only 900 hours or so. This makes me think that he put her into engineers to just tidy up prop and not tell them the whole story and get shock test etc done - The bloke is a liability!!!
He doesn't want to run the group, but will not hand over the reigns, feel that he has something to hide, financial or other wise, not really sure what I can do. Wonder if CAA would have anything to say about all of this, but I would expect that they wouldn't do a lot.
Sorry to ramble on guys, just illustrating what sort of person I am dealing with here!!