I will say that the people who develop HTDP are the some of the people who spend the most time writing about pedagogy in computing education. Felleisen in particularly has written a lot on the subject: http://www.ccs.neu.edu/home/matthias/Thoughts/Developing_Dev...

> The curriculum is too artificial and disjoint from the rest of their CS degree

I would then argue the problem is the rest of the CS degree. Whether HTDP "works" or not, the principles espoused in the course are the same ones you'll encounter over and over again throughout your professional career. As far as I can tell, the only difference is the HTDP (and SICP) folks are introduced to them from day one while others learn through years of experience. And this is the problem about the CS101 course "working for everyone": does it work because you're only delaying the introduction to the difficult concepts endemic to software development? If a student can pass CS101 just by virtue of being able to string together a compilable C++ program, is that really for the best?

Anecdotally, I got a 2 on the CS AP test, which was enough to make me second-guess my major. Luckily, I went to an HTDP school where the professor assured me not to worry about it -- and sure enough, I aced the CS101 course and went on to have a successful career writing code.