You are a idiot. The science is the hard data that they recorded and reported, including the coincidence in age of the depostion layers of the cometary remnants that they report. Whether or not this explains the extinction is, of course, an open question, but one that is solveable by others looking for confirmatory or contradictory data.
This is how science is done, my man. These are world-class researchers and it doesn't get any better than this.
Of course there is competition to publish. But, we are conservatives / libertarians who believe that the world is better off when you have free market competition, and that goes for ideas as well as goods. So, we are supposed to chear this stuff.
Yeah whatever, professor.