Couldn’t agree more. I recently debated this very point a bit with Pete Kemme, when he said there’s no point in doing free weights unless you want to be a bodybuilder. Now, I think his functional fitness workouts are a great way to get a little bit of everything in in a short amount of time, but Pete doesn’t always recognize that a trade-off in quality for each fitness component is involved. If you want great agility, do agility work, if you want greater strength, do strength training. If you just want to be reasonably fit and don’t have a whole lot of time, yeah, OK, maybe do functional fitness, but I think I’d prefer tennis or basketball or soccer. There’s no perfect approach, there’s always a trade-off. Most important is to do what you enjoy, because that will keep you coming back for more, and consistency is more important than any other factor in attaining fitness.
Speaking of circuit training, in my own ST workouts, I kinda come close to a quasi circuit-training style towards the end of the workout, when I’m mainly doing core/mobility/lower weight/floor stuff with no or short breaks between sets and exercises. In the beginning of my ST workouts, I’m doing heavier weights, nice and controlled, even somewhat leisurely, but in the end I’m going through stuff pretty quickly.