Well, the party still survived a 17th level encounter with 5 eleventh level PCs who started out split into two groups about 20 squares apart (although at full strength daily wise, including the wizard's Arcane Gate which was used to join the two groups together). Admittedly it was 17th level on numbers and not levels of foes - there were a few 10/11th level elites but then a bunch of hangers on of various levels from 9 up. (The monsters were from a range of sources, but the non-MM3/MV ones had their damage upped by me in accordance with the new guidelines.)
At one stage it looked as if a PC retreat might have to be considered - there was a river next to the village that they could have escaped into - but taking control of the behemoth pretty much turned the tide.
Now it's possible my group is tactically very strong without even thinking about it - we've got a guy who did his masters in the mathematics of optimisation, and another guy who used to dominate the Melbourne PBM scene, and past members of our group have been Australian M:TG champions - but on the other hand the ranger in our group doesn't seem to get up the DPR numbers that I see bandied around on this forum, yet this doesn't appear to be doing any harm to the play of the game.
So I'm not really sure how the groups who angst about tactical optimality in the way you describe are approaching the game, but that doesn't seem to fit my experience at all, which is that the game is very forgiving and flexible in the sorts of tactical play it will support.
Perhaps my experience is just very atypical. Or maybe as a GM I push the game in a different direction - a GM who wouldn't let an 11th level paladin push through the wall of a burning cottage would have made a big difference in this particular encounter, for example. Likewise a GM who played the monsters as maximally optimised at all times - whereas I tend to play them to maximise the dynamism and interest of the encounter (again, more like a superhero comic or martial arts movie).
My point was that 4e lets you build a character whose tactics would be suboptimal in the real world, and suboptimal in a semi-realistic squad tactics game, but aren't suboptimal in 4e because of the way the PC has been built. This is part of what I have in mind when I compare it to 4-colour superhero comics - a world in which archers and fist fighters can be more valuable combatants than modern soldiers. 4e is like this.
This is true. But I see the tactical/build element of 4e as a technique (in Forge terms) rather than central to the creative agenda. It allows various sorts of expression that a game like HeroQuest wouldn't, but that oldstyle RPGers enjoy (out of habit, if nothing else). But they're a means to an end. What's interesting is not winning per se - that the PCs will win is pretty much built into the mechanics - nor just the pleasure of a cooperative tactical game (a sort of group solitaire), but the how and why of winning, which the tactical stuff helps spell out iin the course of play.
I don't know, but it seems to me to be well suited to it. And probably better suited to it than to classic gamist-via-skillful exploration play of a Gygaxian kind, given the suggested guidelines on awarding XP and treasure, and on scaling encounters.
I'm not entirely sure how those threads are relevant. I certainly don't accept that they show I'm mistaken in my interpretation of my own play experiences, or of the rulebooks that have helped produce them.
Not in my experience, because of the different implications of their action resolution mechanics, as well as the way those mechanics connect with the PC-build mechanics.
A game in which a single hit can reduce a PC from full health to dead, for example - such as Rolemaster, or any pre-4e version of D&D at low-to-mid levels (depending on class) - won't support the sort of play that I am getting out of 4e. In my view, that's why those games are often associated with GM fudging to mitigate unlucky rolls.
