How would you tell the difference between a high linear multiple and a low exponential coefficient? That hypothesis is nearly impossible to falsify and therefore nearly useless. The value in it is simply the encouragement to look for network effects, which are going to cause exponentiality.

BTW, ever heard of word of mouth advertising? That's by definition exponential.

Valid points. We could debate this, but I am already sick of this subthread; the point is I never said sales does not add value or that the value it adds is small, which the GP accused me of, in a rather passive-aggressive tone.