Philip, this is also my personal opinion:

Whats wrong with common sense ? Is there a country that has the trademark on law like you shall not steal ? There isnt. Because practically all human societies tend to come to that somewhere in their history and this applies to many laws and customs.
So, it is the same within this sport: because the conditions are the same everywhere it is only logical that rules tend to be similar everywhere. And may even be similarely recorded.

Any rumour mongerer can be directed towards me and I will give him/her a piece of my mmind about similarity in evolution. This is really childish actually, or is there money involved ?