Well, I couldn't possibly be more against OT[number]s anyways, and I think his point about respecting characters applies equally well to crack pairings and OT[number]s (the second paragraph from the bottom is pretty much pure truth, as far as I'm concerned.)
The part that reeked of crazy to me was the whole 'if it didn't happen in cannon it doesn't count' part, which is ridiculous on the face of it because all doujins exist to portay things that didn't happen in the cannon. There would be no point, otherwise.
I get the desire to keep things in character, but none of the characters explicitly had a romantic relationship in the orginal series, so I don't see why Homura x Kyoko is 'less valid' than or 'degrading' compared to Homura x Madoka or Kyoko x Sayaka (assuming you keep things in character, in which case all that is explicitly portrayed in the original is a strong friendship between Homura and Madoka and Kyoko and Sayaka.)
In the closing paragraph he seems to simply be arguing there's more evidence for HomuMado and KyoSaya (which I don't think anyone is disputing), which seems to be an extension of what overall seems to be an argument to keep things in character (again, I get that.) But If you keep the chracters 100% identical to the original series then nothing will happen that didn't happen in the original series, which again defeats the purpose of making a doujin in the first place. All doujins involve at least tweaking the cannon.
Tl;dr: a few good points wrapped in a lot of crazy, as far as I'm concerned.
On the other hand, he could just be a troll, in which case I put waaaay too much thought into this. :p