You want to force devcoin holders to dump all coins at the beginning of new coin?
Then there should be an enormous source of new coins for conversion of old devcoin to new ones.
I'm personally against any conversion/renewal actions...
I'm saying that if you increasingly reward holdouts, rational holders will obviously just dump all coins at the last possible moment instead.
And at a better rate, which would undermine above objectives (deflation, price etc) far more.
(this is just about what's been discussed, not necessarily my own opinion where I agree it should just be a new project).