That only seems right and makes sense to me. Someone may get ticked about not being able to race, but the rules are there to TRY to keep the field even. Making exceptions to allow one to have a modification the rest in the field haven't done, because they followed the rules, defeats the purpose of having rules.
The real pain comes with local chapters having different rules than the national organization. Say I only ran the locals, hence, I built to those rules. One national race is close enough for me to attend, but I have nothing to race competetively because of this. Now I know dang well I, as a driver, though I'm not the driver, LOL, will not be a threat to anyone, it would be nice if the mower itself could be. How many times can someone be lapped before they look foolish? LOL
So while I understand the reasoning behind local chapters having rules to cater to the local racers, it does have it's drawbacks.
Dale