The application of the rules may be pretty rigid the interpretation of some rules may also be subject to local or departmental advice. So a few variables, every examiner will have a slightly different take on the requirements with the majority of issues being absolutely clear. Some of them try to help and if you are an enthusiast with a decent standard of build they are generally very helpful. To write a rule book which covers every detail is difficult but not impossible and would result in a manual which would need a barrister to decipher. I suspect the examiners are allowed some leeway as build quality must affect the result. If an examiner sees a basic shed presented he may need an escape clause, however from the majority of results on this site they are reasonable in there approach and we tend to be a little over reactive when we haven't read and understood the rule book also its basically a competence test and we don't like those. A radius is a radius when all said and done, if the examiner has disregarded a minor in light of a good build we should be applauding sound judgement. In my case they rejected a carbon mods dash with a large radius on the bottom edge, it wasn't the required amount 19mm I think and they were correct, a simple application of some stick on foam sorted it. All minor stuff but necessary to maintain a good standard of car production. I am mystified by a few of the rules regarding sharp edges and the locations of those but in reality its quite simple, read the manual and other posts about general issues but also consider specific issues which various VOSA stations may have raised just in case. I also found the VOSA technical advice chap to be very helpful especially regarding the need to have CE marked harnesses with no mention of FIA acceptable items, an old chestnut but at the time could have been a fail as the rule book did not list that FIA exceeded CE.
Its an expensive test of our ability to build a car and a necessary one, we have all seen the results of the not quite competent amateur and the danger that could cause to themselves and others.
Bob