There are some strange design decisions in PC2 but IMO that isn't one of them. Your race wasn't ruined by the limiter but if you don't have one mapped then your race will almost certainly be ruined if the limiter isn't automatic. PC2 disqualifies you if you speed in the pits. Nor do I understand why you were worried about hitting the limiter by mistake. If you were so keen to not use the limiter for the historic cars -why would you do it by mistake?