There is so much vitriol in Erechel's post it's not worth responding in detail.
I think there's a lot more ESL than vitriol.
I am hoping you did not mean that the way it actually reads.
I meant it as "keep running 5e, and you'll acquire the familiarity and confidence to modify more of it."
The average player is more munchkinesque in 4th edition. An average 3rd edition player (and I've played with many non experienced ones) certainly is not near as effective as a munckin one, because the powergamers were scarcer as it tends to be a game were rules and options were monstruously high.
This might be something peculiar to your location. 3e was complex and imbalanced, system mastery required a fairly significant effort, but the rewards were very high - but it wasn't difficult or rare to acquire such mastery, and the internet was full of broken combos and detailed optimal builds you could lift if you wanted to. Thus, system mastery and its effects were pervasive in 3.x - probably one reason why the on-line was adamant about following 'the RAW,' as letting DMs get away with changing or re-interpreting the rules would dilute the value of system mastery.
I don't know if it is the case outside my country, were D&D books are expensive and mostly in a secondary language, but here most players don't know most rules.
I can see how that would lead to less powergaming at your 3e tables.
What I'm trying to say is that to become an average 4th edition requires a level of metagaming mastery not present in prior editions, hence the dissociated dynamics as the core.
Again, it sounds like this is a language barrier issue. Not only is 4e written in English, but it leans heavily on jargon. To a native English speaker, it's usually pretty easy, if you're willing to do it at all, to learn the jargon definition of keywords and from there the game is very clearly written. There's not a lot of need for interpretation, and you don't need to memorize spells, monsters, items, or other powers, because you can easily understand them on a first read-through, nor does a DM need to be intimately familiar with all the PCs' powers, because he can count on his players being familiar with them, and can resolve and unfamiliar one easily at the table, even if no one had ever looked at before.
But, yes, I can see how, trying to translate 4e, missing the use of jargon, and instead memorizing it so you could help everyone at the table build and play their characters as if it were as inconsistent and unclear as an earlier edition might make it seem even more daunting.
Its interesting how the same game we have all played can have such radically different results in us.
For many of the reasons listed above where someone found 4e dissociative, I found dynamic and the opposite of dissociative. 4e allowed me to visualize and creatively imagine what was going on in the action better than the majority of all RPGs, not just other editions of D&D.
Nod, 4e's fairly obscure 're-skinning' rule, gives you permission to re-imagine how powers work and look, as long as you leave the mechanics alone. If you can embrace that, it gives you the perception of openness to creativity that you experienced. If you can't, then you could be disappointed with or confused by a power description that doesn't mesh with the way you'd imagine the mechanics translating into imagination, since you don't realize the description is just a suggestion, and you can substitute something that works for you.
It's still a stretch from that to the 'dissociative mechanics' edition-war rhetoric, and, indeed, the article than coined the term actually did re-define power descriptions (actually that of the whole source), in order to make them dissociative, on the grounds they were 'unrealistic' as presented. So the option of re-skinning could go both ways. You could use it to paint the image you were going for, or to sabotage your own enjoyment of the game.
I also feel 4e requires the least amount of system mastery IF you are a player. It is actually a very simple system.
It's fairly clear and balanced, which can make it seem 'simple,' in one sense (easy to use). It also has a lot of detail and 'moving parts,' so as a system, it's complex. Complexity can seem simple or complicated depending on how it's presented, and how the reader approaches it. A player looking at 4e and trying to figure out which race & class best fit a character concept, then build that character, is likely to perceive a fairly simple system, by the time he's done, he's looked at a few obvious choices of race, class, powers & feats, and probably has a good handle on the ones he's chosen. Similarly, a DM who just wants to run a module only has to learn how to read a monster entry, and handle the mechanics of the game - one building new encounters would have to learn the encounter building guidelines.
OTOH, if you approach 4e from the perspective of trying to find the most powerful classes and feat/power/item combos, you have to look through /all/ of them, at least a full read-through of everything, and that's a lot of material. You experience the full complexity of the game, that way.
Not too familiar with that ever happening either - is that actually a rule, or just a dm "ruling?" If the latter, I would say its poor DMing more than anything else. 
