Think about it. One design rules - what do they seek to control? and why can't they also control the courses? and why don't they? Consensus. Best practice. Practicallity. All unregulated. In a similar sense, the use of mommie boats works on consensus. If that consensus is broken through extreme use, it will have to be regulated or banned. If RC's started laying obscure courses that annoyed enough competitors, courses would be regulated too.