As we get older, there is an increased reluctance to embrace change, even if it is for the better. That is why rules for a sport involving older people should be well thought out before being put in a rulebook, as there is bugger all chance of getting them amended later, (even if they are wrong) because you will never get everyone to agree. The problem with the MA pre '78 rules is that they were copied word for word from the AHRMA "Historic class" rules, presumably because no-one here had the imagination to write up sensible rules for this class. Just be thankful that the AHRMA "Ultima class" rules were not copied for MA's pre '85 class, as they are written to try and change history and create a imaginary level playing field, where you can race an '84 CR500 Honda or '83/'84 KX500 so long as it doesn't have the standard disc brake front end. The thought of an '84 KX500 running around in pre '85 class with a drum brake front end just seems totally wrong to me.
Maybe I just have "issues" with authority, as there always seems to have been rules that I thought were plain stupid, even way back when I first started racing. I can still remember reluctantly having to rivet rectangular numberplates over the oval ones on my brand new bikes, because that was the rule at the time. Which genius in MA ( or ACU , as it was back then) came up with that brilliant idea ?