Agreed. I mean, the pubs are ripe to split yet they won't. The main reason is that whoever split to make a third party would find themselves completely out of the circle of power that allows our system to be a 2 party system.
We would have to completely blow up the private companies that handle the debates, much of the polling that things like the debates are based on, etc.
There is no way, short of some legislation, that would make a third party feasible in this country, and the legislation will never get proposed or passed because two party system.