No, that many premixes (one of the WOs/DVDs has 30 [!]) definitely seems excessive.
I REALLY appreciate when DVDs have premixes, though, esp. when there are shortened versions of the WO or ones that isolate certain moves -- just cardio moves, just the strength moves, just upper body strength moves, just lower body strength moves, etc.
But, no, 24 premixes for one WO does seem like overkill. (I find some of Cathe's premixes can be really superfluous, as well, like the "double time" or "extreme" premixes/options, which are basically just repeating/doing the WO two times in a row, something the user can do themselves just by restarting the DVD.)
I think maybe, though, this series has so many premixes because she has SO many add-ons (Calorie Crushes, Pyramid Pumps, Extended Stretches and Bonus Abs). I think with that much Bonus material, the combos are almost endless, and I think they're just trying to anticipate and accommodate users needs/desires as far as "mixing and matching" goes, which results in an inordinate amount of premixes.
I have to say, I'd rather there be too MANY premixes than not enough, though. Most of the time, most of the premixes don't really catch my attention, but looking through some of premixes she's posted is peaking my interest and curiosity! I'm already looking forward to trying some of them out!