Right. As long as we ignore the actual success of an edition with the OGL and lack of comparable success from one without it, and ignore what Ryan Dancey has to say, and so, etc.
So, you believe that 4.XE tried to duplicate the success of 3.XE but don't recognize some difference in their successes. Plus, you still insist on using some odd timeline where 3.XE is five years instead of eight, and 4.XE is somehow five years when we're still shy of four years.
What odd timeline? 3e lasted 3 years. 3.5 lasted 5 years. 3.5 IS A NEW EDITION OF THE GAME. It replaced the previous edition. It is not the same game. You cannot use 3e material at any official Organized Play event after 3.5 was released. 3e support ended the second 3.5 was released.
It's pretty disengenious to pretend that 3.x is all one big happy family.
/edit to add - 5 years is pretty easy to calculate MarkCMG. Release date June 2008. 5e release date 2013. Last time I checked, that was 5 years.
It's really difficult discussing things with you when you don't want to even agree on some things that others on both sides of the discussion would regular not dispute.
What would we not dispute? That there exists a 4.5 edition? Well, I'd say that's in pretty strong dispute wouldn't you? That 3e and 3.5e are separate entities? I'd say that's pretty obvious on the face of it.
See, while I agree that 3e did very well, my argument hinges on the idea that 3e's success and 4e's lack of success had anything whatsoever to do with the OGL. If the OGL was pushing sales of 3e the way you are claiming, then why did 3e get replaced so early? If WOTC were still banging out books at the same rate as 2000, then wouldn't they keep on with 3e?
But, apparently, sales tanked pretty quickly. Was that because of the OGL and the mountain of crap that got produced? Maybe. I don't know.
All I know is, the non-OGL 4e is going to have a half life longer than 3e or 3.5. Six years between editions isn't exactly a rocketing pace. Seems pretty standard. How much of an effect does the OGL apparently have on the longevity of an edition? Apparently none. The non-OGL version lasts just as long as the OGL version.
And, let's not forget, 4e wasn't exactly a failure. A second print run before the game is even released is pretty healthy. IIRC they did go into a third print run as well. 4e was a failure if you presume success was the level they pitched to Hasbro. As an RPG, it did pretty darn well.
But, all this aside, the basic question remains - how much of an effect, if any did the OGL have?
Until you, or anyone else, can answer that with anything other than anecdote, it's pretty difficult to say whether or not the OGL was a good thing or not.