We at Wonkblog watch (and participate) in a lot of debates about new research. And we'd like to say all those debates adhere to the highest standards of rigor and are motivated by nothing more than a search for truth. In reality, it tends to go more like this:
Obviously, these arguments are often correct. Experimental studies really are better than quasi-experimental studies which really are better than regression analyses which are certainly better than nothing. Big, broadly representative samples really are better than narrow ones and it is important to have multiple studies back up a conclusion. But given that people tend to read what they want to read in research, these points tend to be used more as bludgeons than as good faith critiques.