I've given this some thought. I've played it, both badly and well. I've read a bunch. I've talked to its developers and knowledgeable business people. I've built a couple setups for play.
I can only describe the cultural discourse about it as mass hysteria. Almost no one seems to have played the game I'm looking at.
No off-the-cuff, "everyone knows" statement about its financial history is accurate.
Plus there's the whole, "It sucks," "Really?" "Well actually it's really good, it's just not D&D," dialogue, which is like talking with those allegedly wise cosmic aliens on Star Trek, when they eventually ask, "But ... but ... what is this 'love' you speak of?"
The idea is to ignore all sense of implied setting and merely cherry-pick what you want to play, flushing "D&D" as a category out of your mind.
I have two such templates built with some care. The first, called "Barbaric psychedelic psionic ectoplasmic 4E D&D," now looks a bit different from those earlier discussions - see attached. If you have the texts and time, try making up a character for what I've posted.
Please note that not one rule is altered or even tweaked. Please note as well that my choices for what to use and not use, and which options to highlight for favored use, are very mild compared to the alterations and specificatons found in most OGL adaptations self-designated as OSR, relative to their starting texts.
Talking about this sensibly taps into other discussions from around that time, including my initial experiences as a 4E player which are linked back in the above discussions, Pink Slime and the various D&D-as-religion threads.
I'd like to pick up on those here but mainly through omission. Instead of what 4th edition is not, or allegedly not, and instead of what D&D is or is not, let's talk about this thing I'm presenting. Vincent? Your clouds-and-stuff diagram thing? Anyone else, your notions about what role-playing is and how it works? I'd like to compare my thoughts with yours.
Furthermore, look here! It’s my current game of the same idea, now more refined and built with a better understanding of the rules. Ross, James, and Gordon are the players, and I’ve attached the handout they used, and character sheets are forthcoming in a bit.