Caveman - that guy's style is fine and probably profitable for the fishiest low stakes games, but as a general tactic I wouldn't encourage it. Better players are going to bet when they're ahead of you and fold when you suck out & play back at them hard like he does; and as you move up in stakes you're going to be in more games with better players. Or at least, tighter players. As a general approach to poker I can't really endorse it.

However, I do find a lot of room for calling. I call a lot in position on the flop (what is referred to as floating) against standard TAgg players to see if they slow down on a later street and give me a stealing opportunity. I call a lot in and out of position against smart, yet hyper-aggressive players, because they tend to keep hammering at pots as long as no one raises them - I get more money out of them by playing like a calling station whenever I have anything decent. I call a lot pre-flop in loose, fishy games when I have hands with potential and I know raising won't thin the field, and c-bets on the flop would get called most of the time anyway. And I call to control pot size and to get information - for instance on a hand where I raised with QJ and flopped a pair of queens, and then someone bet into me on the flop with no obvious draws out there. In that kind of situation I think my hand may be good, but I'm not that interested in defining my hand quickly or playing a big pot in a questionable situation; I just like to call, see if I can slow them down and get a cheap showdown. I'm more likely to raise or fold the turn depending on how they respond to my first call.