I would be interested to hear views on the quality of the scholarship in the essays on the same site.

It isn't my cup of etymology, but the author's intentions certainly appear laudable.

He says he wants to present all of the "minority" arguments in favor of a single source language in one essay with cross-references.

He is inviting visitors to contribute to the effort.

It sounds like he is performing a service for anyone who is interested in a speedy immersion into an esoteric subject where the scholarship is scattered and only the initiated know who is saying what, and who is whom.

If he achieves what he is setting out to do, the visitor can screen out the dogmatists with ease, separating the wheat from the chaff. [Of course, there could be a kernel of value in some of that chaff.]

Who can fault the author's ambition or his approach?

He begins by stating his particular prejudice and then he concludes his introduction with this:

I will be providing links to counter-arguments which the reader will be able to access through this central essay --- as well as the arguments presented by its opponents --- so that anyone may obtain a balanced view of the question.

That's pretty fair, isn't it?