Canuck75 I'd be interested to know as well.
I think the reason the Key Sound™ is so effective
when articulated correctly is because it is the lowest sound the human voice can make, therefore it vibrates the entire trunk of the body, including the lowermost area, aka the root chakra, and awakens the response from the root upwards.
By the way, when are you going to post your Key Sound™ sample to the free Validation Area so I can let you know whether or not you are articulating the actual Key Sound™ correctly or not?