It would, yes. And that's still before process improvements. There's so much that can prevent attaining idealized performance, though, that the only safe bet is 40%. Which is probably why AMD chose that number and has been so adamant about sticking with it.
For example, AMD has only stated ">40%" for the server CPUs, when we all know it should be >60%, since Piledriver is the reference - which is two full generations behind Excavator, which is an easy 17% ahead in IPC... They're definitely playing it safe with the numbers. And we should all do so with our expectations.