I'm with you here. Listening to the experts is good advice in any aspect of life.
I've personally found the "hypertrophy" days where you use more load and less reps are the problamatic ones that take quite a long time. 10x3, 75s rest with 4 exercises, and adding in the loading/unloading weights and all that stuff, sometimes the workout can take nearly an hour or over which seems counterproductive, as I've read that working out for more than 45 mins or so is, to put it short, not optimal (something to do with cortisol if I recall).
The other days where there's more reps and less load are actually quite fast, like 30 mins, as there's not that many sets.
Meh, still, if its possible, I would prefer to use supersets.