The approach described is common. Dan Pfaff uses similar as does some of the other former LSU coaches. They typically do tempo stuff on Sat. So, early in the season the Sat runs would be low % of pr repeats with short rests, ext tempo if you will. This progresses to Int tempo/CSW then progresses to speed end. This approach has been very successful as well.
I do ext tempo or alternative, so does Mangiocotti. His general days are what most on here would call ext tempo or equivalent. When he has Int tempo written it is on a hi day.