To say it forthright: It's advertisement. There is not the weakest hint that esc. actually is so unequally better than c., as the claims suggest. It is an info page and not a stage for advertisement. If the studies were provided (if they exist at all!), the reader could judge himself and he could also have a close look at their (potential) weak points. 
I have no problem with unreferenced texts, but my credo is: provide reliable refs or remove the passages (to the talkpage or nirvana resp.) if there is a single one who mistrust them! Quality comes first!P.S.: I am (quite) well aquainted with WP.