>For software Copyright is a far better instrument. Let the one with best implementation win... That's where the cost is: Implementing, testing, shipping, maintaining. Protect that.

But this is minimally protectable, and you can copy the idea just not the exact implementation. Copyright does not have a 'doctrine of equivalents' equivalent. It also supports independent creation. Copyright also does not cover functional elements. You cannot copyright an idea, only the expression. So maybe you can elaborate more on why your point makes sense?