And yet it stacks on top of your plate mail which gives now gives you an extra +2 to your AC over your non-dodging banded mail wearing compatriot who spent his feat on power attack and an extra +1 on his sword.
Oh. You're one of those; The CharOps types. You probably thought the Expertise feats were required in 4e too because the absolute highest possible number is always best. You take no consideration of the opportunity costs, just the absolute value.
Also, why is the one guy in banded-mail? If the guy who took Dodge can afford full plate, certainly the guy who didn't can too. Oh, right... you're trying to distort things so Dodge doesn't look like the garbage it is and associating +2 with dodge makes it seem less like garbage.
So the actual difference is +1 AC against one attacker per round. Three orcs attack you and Dodge MIGHT matter for one-third of the attacks (if you chose the right orc as your "dodge buddy"... that orc may have attacked the guy next to you instead so you get no benefit at all). By contrast the non-Dodge guy gets +1 to every attack he makes... or takes a penalty to hit to gain twice that bonus to damage (because power attack is only worth it with a two-handed weapon).
Also, since you seem to have missed it; the point of comparison about armors was putting a gold piece value on the cost of +1 AC; it's not much. The point was that for just 1250 gp (the cost difference between banded and full-plate) you could get +2 AC vs. every attack. In 3e that's chump change past level 3 and you're trying to sell that spending one of only SEVEN feats should gain you the benefit of spending about 625 gp.
Also, it's cute that you think anyone with the Dex to go after Whirlwind Attack (the only reason to even bother taking Dodge) would choose full plate over a mithral breastplate. Full Plate caps your DEX to AC at +1. Even mithral full plate is only +3 (Dex 16) and still reduces your speed to 20ft. Mithral Breastplate lets you use up to a 20 Dex to AC (+5 bonus) and (relevant because Spring Attack is in the chain) lets you have a base speed of 30ft.
Your invocation of "inarguably trash" indicate that you must have never experienced the full range of trash feats to be found within the complete 3e library or then we could argue about getting +3 to your hit points.
Just because Toughness is bad (for fighters; for a starting wizard it's nearly doubling their hit points and has been credited by many wizard/sorcerer players I know with keeping them alive long enough to get the higher level spells) doesn't make Dodge good. It just means it's not THE worst choice for a fighter; just one of many possible bad choices.
And this again proves my point that your evaluation of Dodge is completely divorced from opportunity costs. +1 AC can be a good thing if it's valued appropriately. +150 or 625gp for improved armor? Super. +1000 gp for a +1 enhancement bonus? Worth it. +2500 gp for a +1 deflection bonus? Worth it in a high-magic/undead focused campaign... not as much in a low/no magic setting where touch AC won't come up much.
A conditional +1 for the cost of one of only seven feat you get? Not even close when alternate choices include power attack, cleave, expertise, improved disarm, improved sunder, two-weapon fighting, etc.
That's why I say it's inarguably trash... actually the entire fighter class in 3.5 ranks just above garbage tier (tier 5; can't even do its one job all that well) to the point that the NPC Adept class (no class features and only a partial caster like the bard) is considered a more valuable addition to the party than a fighter (the Adept is tier 4).