Isn't all this drama just misdirected since 400 Mbps is coming in the summer. 150 Mbps is just too low for 4:2:2 10bit.
...But you're comparing the bit-rate of an IPB CODEC to an ALL-I CODEC, so the difference may not be what you expect it to be. Raising the standard 4K IPB bit-rate from 150 Mbps to 200 Mbps could make a difference. ( remember how much better GH2 hacked footage became once the recording bit-rate was raised )