When half of BTC holders will have exchanged their BTC for BCH, then it will be a 50/50 split. Until then, you need fresh money to add value to the new chain. I think this is quite intuitive from a macroscopic, detached point of view.
Sounds like you are saying that there is currently something other than the 50/50 split.
Can you elaborate more on "half of BTC holders will have exchanged their BTC for BCH"?
When I say 50/50, I mean value wise. So I actually meant "half of the BTCs have been traded for BCH".
At the moment, the number of extant BTC=BCH.
But the value? They can say 500$/BCH all they want, but as long as I won't (or can't!) get 500$ for each of my BCH, it's just talk. Words are wind.