This is a super interesting post, so I hope you'll forgive my disagreeing with you on a point of detail. Like many posts these days I do ask myself which game people talk about when they mention 4E. It's certainly not a game I've played that matches the description. Off we go...
Yes, you'd think so from reading the books, but it ain't so.
Let's start with a basic question. Ask yourself:
when do players try to make the playing field as unbalanced as possible in their favour?
Easy: when the odds are crazily stacked against them.
What happens in our 4E home games is that the difficulty of encounters are super swingy. When we know there's a chance at an even fight, we start ravaging and throw ourselves in the middle of a - mostly unprovoked - fight, with no second thoughts. Hey, my PC is a barbarian, what do you expect?
But what happens when we stand no chance in a fair fight? That's when party brooding begins, plans are forged, and we unleash things on the world we wouldn't want to have visited on ourselves. The ensuing mixture, if you like, encapsulates Fafhrd and the Grey Mouser. They excelled at playing it unfair - after all, you gotta backstab the world before it backstabs you! - but they sure also liked throwing themselves into mettle with only half a mind.
To prove the point, here's an example from one of our 4E games, from last October or so - I mention it because it's a personal favourite.
(I've posted this on another forum some weeks ago, and you'll see that like you I use Kellri's signature phrase below.)
We had to re-capture two spies who had taken refuge in a bandit camp. Problem: our party is hopelessly outnumbered by the bandits (5 vs. 30).
So we cast a Tenser's Floating disc ritual, built a wooden hut on top with a 'window of safe escape' which means anyone jumping out of it falls to floor under the feather light spell, thus slooowly and safely to the ground (this is an item from Adventurer's Vault 2). We filled the hut with combustibles (oils etc).
Ok, off we go. Party goes inside the hut - remember, it's on top of a Floating Disc - and wizard steers the hut over the camp (it's night), ca. 100 feet above the ground. We all then jump out of the hut, the wizard terminates the 'floating disc' ritual and as the hut roars towards the ground he sends a fireball after it...
..and it's" Fantasy F*cking Vietnam", to use Kellri's phase. The exploding hut detonates on the bandit camp, there are lakes of fire everywhere, as we float down we keep firing arrows and spells on the bandits (now slowly awaking), and kill the rest once we hit the ground. It's dirty, but spectacular, and the fight takes only 5 minutes of real play time to resolve.
You think smart, prepare the fights instead of them setting up you, think outside the powers, and you can play 4E quick, dirty, and spectacular. Some of the best fun I ever had with D&D, and this type of thing happens in every session. Quite remote from the received wisdom as regards "4E in play" you find in the forums, so there you have it.
In terms of time spent, this was a three hour session, the majority of which was spent on planning the disaster. As stated, the final fight once the PCs hit the ground was over in hardly no time. And that was all using 4E rules.
The reason I find 4E such a rich game is that it added what you call "War as Sports" to the RPG. It didn't take anything away because, as you can see, it's all still there for the taking, involving only published material no less.
Now, I totally agree that the core books could have given more advice about "Combat as War" for those innocent souls who have never seen it. But in our age group, insanely immature as we get once D&D hits the table, with an adversarial DM and a couple of pints downed? We're there, buddy, we're there.
And you forgive me if I say that these are things no designer can write up for you, and that you'll never buy that stuff in a book, no matter what edition number or label on the cover.