Here is a laymans attempt at answering the OP's question.
I have a guildmate that runs a level 20 WF Fighter Kensi THF Greatswords with all of the fancy feats.
I run a level 14 WF FB Barbarian THF with Greataxes.
We have compaired numbers and I can put out higher damage per hit. When he activates Haste Boost he will get more attacks which equates to more damage however I still have higher individual numbers.
He enjoys his fighter. I enjoy my Barbarian. Enough said.
Don't factor rage pots in your thinking. Barbarian rage is a very different fish, and stacks with rage spell/pot. I can't give you specifics, as I only have a barb at cap, but I think a barb is basically a 0 ac power machine with lots of hit points, while a fighter is more versatile, due to access to a lot more feats. So you can be tactics based, ac based etc...
It's a game. GAME! Only a game. say it with me now - GAME. There. That's better.
They're the same in that rogues are higher dps.
Absolutely....
one awesome crafting idea would be to take numerous small, medium, and large infernal chains from the Shroud, and be able to craft a retractable chain/yo-yoish kinda thing ....
then strap it to the back of a a dual wielding, halfling rogue and then duct tape some weapons to their feet too...... (think of the James Bond movie, Octopussy)
now that..... THAT.... >>THAT<< would be some ranged, returning DPS for melees.
I've just hit GH on my fighter and an ac of 37ish is pretty much irrelevant. I would think ac on a barb in excess of that would be difficult to achieve without a heavy gear investment. At that point DR and things which give displacement miss % are much more important. That is when a barb will really start to shine imo.
Plate looks cooler
Implying.
The part of my statement you did not put enough weight on was "without too much effort". A DPS Fighter is going to have Kensei - the Reflex save there is no effort. A fighter has more than enough feats - picking up a saves feat is practically no effort. Now the barbarian has to keep Improved Uncanny Dodge up just to keep pace, AND has to lose DPS to do it.
I run my cleric through epic traps, let's be serious. Who cares about traps?
The way this game stands now, equally geared fighters will generate more damage than a barbarian. There's no situation in the game right now where I run out of haste boosts, so using haste boosts as a justification for "short term" dps is a faulty argument.
Using umd while dishing out 100% dps is much more eficient than sucking down silver flame pots and having a constant -10 str on a barb, Your'e to-hit and tactics suffer, both of which I won't have on my melee.
All you have to do is a general overview of the past life feats and enhancements, and plus all the fighter bonus feats comes down to this very simple equation.......
Barbs are savage brawlers
Fighters are tactical experts
This is just a raw overview.....not including gear or the mindset of the person pushing the keys while playing one or the other...yes when it comes down to that certain Barbs can definitely be more tactical than a fighter......but then your just going off into a bunch of variables.
Relate it to Sorcs and Wizards......
Barb=Sorc
Fighter=Wizard
Kensai - saves? Kensai - saves? If anything, defenders have better saves because of their stance.
The ~+4 to reflex you get from all the feats (really, did you take lightning reflexes, luck of heroes, AND snake blood?) is still less than uncanny dodge, which barbs get for free.
If you wanna talk saves - play a pally.
Barbs have raw strength. This provides them their accuracy, damage, and tactics.
Kensai fighters get these from enhancements, feats, and class features.
These go towards the same end - both will be high dps and have good tactics (if you choose to focus on them). Kensai may be tied to a certain kind of weapon, barb gets more benefit from glancing blows, rages last longer than hasteboost in worst case scenarios between shrines, etc.
Ive got a fighter and a barb sitting at 18th level. I call the fighter my "mad cat" because it just has more toys and is better all around in my opinion. But when you get right down to it, I can't tell which does more damage since they both blow me away.
Fighters (kinsai) have a huge strength boost that gives the same benefit barbs get without the letdown of the cool down time. But barbs lose that at level 18 and you can constantly rage for close to 20 minutes before resting.
At the end of the day, they are too close for me to call. They both kick butt and both have their definate strong points and not many weaknesses.
The Fockers of Argo
LOOON (Rogue); Reaperbait (Warlock); Eatuhdiq (Sorc); Fuglymofo (Barbarian)
Buttscracher (Arty), Hobaggin (Druid)
Well it's sort of Conan vs Highlander isn't it?
If only my 1/2 orc barbarian could wear a fur thong...