I'll just throw out my experience. When I saw the length of the unit and the PT in the middle, I immediately thought of it as two units. I had already started with programming (from another curriculum) and came to this unit with about 4 weeks left in the semester. So I got to the midpoint, through HTTP to the practice PT, at the end of the semester. This allowed me to start fresh with the second half when we came back in January. And in terms of lesson content, the break seems natural as well.
I do like Kaitie's idea of breaking it in half with programming and will do that next year if the timing can work it out that way.