Bullshit, Privat Pile. A cam may fail in a parallel-sided crack. A cam will never fail (unless it walks out of position) when placed behind a constriction.
At a belay, a bomber nut is always better than a cam in a parallel-sided crack. This just seems obvious. But then, who is going to avoid a bomber nut placement in favor of an all-cam belay? I also think three pages of opinion and emotion have been devoted to the wrong question. What I see as an extremely hazardous and all too common practice is when climbers belay directly off of the anchor, regardless of its quality. I think the importance of the belayer's stance should be discussed instead of this gear-freak discussion.
Dammit, SlangSmackTalker! Our whole culture is based on the externalizing of problems.
And you...you! Come along talking about PERSONAL RESPONSIBILITY , Mr. High 'n Mighty. What kinda hippy commune you runnin' over there, Dammit? What with Rat, Rolf, FeralPig. Jeez, who knows what goes on...
I mean it, Mister E W. If the belay anchor is so marinal that it can't hold a few hundred pounds, maybe a hip belay can relax the anchor strain. Maybe a c-4-Stealth-enhanced stance offers more security than nexted Aliens.
Rat....Rolf......hippie communes.....you don't know who you're talking to (but I know who I'm talking to).