What a fun thread! You can usually tell who the truly knowledgeable people are b/c they are the least likely to be idealogues about their training methods. The more you learn, the more you come to realize that diff't programs work for diff't people and although human bodies must all follow the same gen'l laws, there may be multiple methods, all of which work, and all of which will get you to your goal.
The 5x5 is great but even madcow and Glenn have said it's just one way to grow and that it's great (a) for packing on mass on beginners & intermediates, and (2) for it's value in teaching people how to design/adjust programs in general (e.g., it's a great teaching tool b/c most people have crappy knowledge from BB'ing mags, etc.). I think lots of trad'l bodybuilding folks are following supercompensation splits that are, obviously, working for them. But they want that style of work and that style of growth. They may specifically avoid a compound exercise b/c it's too taxing and they prefer to use more isolation-type exercises to fully exhaust each specific muscle. If it's working for them, that's awesome. And I'd say it does work for quite a few people. Here's the thing -- you can continue following the "5x5" principle of adding weight to the bar (i.e., progression) AND still follow an old-school BB'r split. There are plenty of valid reasons for NOT sticking to a strict 5x5 program and I'd say this is especially true for the pure bodybuilders among us who truly care only about aesthetics. But if you're a 160 pound guy who wants to get on stage, you could probably gain a lot of mass in general from a 5x5. However, if you're already nearing that professional level, you may not want the 5x5, heavy compounds, over and over style.
My point is that the 5x5 is fantastic for lots of people, obviously, but it's still just another training style and although it's principles are sound, just b/c you're doing iso/hypertrophy work doesn't mean you're automatically IGNORING the gen'l principles that come out of the 5x5.
FWIW -- I like BB rows and chins. LoL But I'm pretty scrawny so can't say that they are the only way to get big.