I agree that you can find a way to bolt good UI over anything, much as we've done amazing things with the "stateless" web. But there is a large truth underlying

I agree that you can find a way to bolt good UI over anything, much as we've done amazing things with the "stateless" web. But there is a large truth underlying his argument, which is that you will have much better results if you design for usability first not last, and also that the amount of work required to make good usability can be an order of magnitude more than the amount of work required to build a raw API. My big takeaway when I first read it was that you can't think that 80% of the job is the implementation and that the UI will be 20% of the work to be done after you hammer out its functionality.