tl;dr: I think that agrees with what I was saying, for some definitions of the word "separated".
The two activities credentialling and learning are strongly related, because testing can be a good way to give feedback during the learning process, in addition to being the only scalable way to filter masters from novices. As far as I can tell, apprenticeships and co-ops don't scale today. Interesting if they could.
I don't think it harms Udacity to run both - a free tier for people to get their feet wet in CS and explore through a lifetime of learning, and a pro tier that gives the equivalent of a Master of Science with certificate (ie, classes only, no thesis). The free tier allows unlimited retries, has no deadlines, and encourages self-learning. But the pro tier separates the wheat from the chaff a bit, is strict on identity, is strict on plagiarism, gives one-try test grades, and has a minimum bar for certification.
You could probably make the divide between free and pro in a much different manner than I just did. I think I gave a pretty old-school university way of thinking about the problem. Of course they are not confined to think this way.
The materials for both tiers could be very close to each other, to the point where it would be wasteful to separate instruction. That's why liberal education and professional education get smushed together into higher learning today. Maybe Udacity can separate out these two in an interesting way.