Others have really covered the substantive issues, but just to clarify a few things about where I'm coming from personally ... this is not so much a direct response to coloradoan, but to give necessary context for others who might be reading - especially those who are new to the 'Slide and/or this issue:
I don't/didn't disregard Ilya. He clearly knows a lot about optics, optics manufacturing, and how eyes and brains process information. I've actually learnt a lot from him. I'm just clear about what he does - and doesn't - cover in his optic reviews.
I'm not after a "guru", and I doubt most on Rokslide are. I have some different opinions from Form, but he's always taken the time to answer questions I have with civility. And - here's an important distinction - when I hear Form talk in what seems like fairly absolute terms, it's usually based on his direct experience, and he can usually present evidence to back up what he's saying. Ilya, on the other hand, often speaks in absolutes about things that, if you listen carefully, are actually only his opinions, preferences, and so on. There's a big difference there in terms of not only style but context/credibility of the positions expressed.
As for my use of "ill-mannered", the most common term I hear Ilya use about (other) people he disagrees with is "He doesn't know his ass from his elbow" ... it might just be his style, but personally, I don't find it particularly useful. While I don't think he used that pat phrase when speaking about Form, if you listen carefully, he did cast some aspersions about Form (even though it was about things he acknowledged he didn't actually know about); this was unnecessary in the context of what he was talking about, but appeared to be designed to undermine Form's credibility. It was not only therefore an ad hominem attack, but also a bait-and-switch from the issues being discussed.
Most importantly, I don't think any of us here need or want to turn this into a "Form vs Ilya" issue - Form does what he does, Ilya does what he does. Their expertise, experience, and "missions" are clearly different.
How about we all learn what we can from whom we want, and leave aside that which we don't find useful?