What are consequences of "merger necessitates removal of ...

[Alan Cox]

> Sure, nobody's holding a gun to your head, but if you want to have all the 
> security updates, you *are* forced to do the major version upgrades.

Or get enough other people together doing fixes as a group. Its a hard
and expensive business and it gets harder and harder with time. Nobody is
stopping groups of people getting together and doing the work though.