Well, Kiefer is very anti-cardio. But you have to take that with a pinch of salt, given his bodybuilding focus (and the fact that he walks around at over 230lbs and wants to keep it that way). His iron-clad belief is that steady state cardio (as opposed to HIIT, Crossfit etc) makes the body more efficient, which makes it want to retain fat. The logic and the science is pretty good there. He has other reasons, but that's the main one - it just doesn't work well for fat loss. I've pretty much always said that you should do that stuff if it's your sport, or you just like it, if you find it relaxing or whatever, or you get some achievement buzz off of it, but that it isn't going to be of much use to anyone for weight loss if you are weight training and eating heavy on the protein/fat end of the dietary scale.
If you are restricting calories, you'll likely lose more weight that way, but you'll lose the stuff you don't want to lose. (You probably recall Kiefer's bit in the book about how that creates a negative cycle, where you lose a bunch of water, lean mass and some fat, then slack off and rebound hard to the same weight as you started...except now your % of lean mass is lower than when you started! Bad times. So the extreme ends of your two branching paths there are emaciation with pitiful lean mass but minimal body fat and likely terrible health, or obesity with pitiful lean mass and likely terrible health...)
Also bear in mind that Kiefer is preaching to highly dedicated athletes who have been conditioned to do heavy cardio for years, thinking it is the only way to go from 6% BF to 4% in time for their bodybuilding meets or whatever. So I think he lays it on super-thick just to get people to do LESS cardio than they currently do. And to get the wider mass of Americans who ONLY do cardio to think about maybe lifting something instead.
Right now, I think Mark Sisson's attitude is more realistic. He talks about a certain weekly energy budget that you can (and should) spend on cardio-type activities before it starts to become a negative. Everyone's spot on the spectrum will likely vary somewhat too, and it's not like going 1% over will suddenly zap away all your muscles and land you in hospital. You can probably do 1-2 hrs / week and still gain strength and lose fat. Would doing so help or hurt? Well, it depends what you're doing the rest of the time. If you are doing a lot of walking, manual labor, playing in the yard with kids, playing pick up ball or whatever, you may well not need to spend any extra time doing that stuff, and the more you do, the more you might be hurting your health/fitness.
