I re-read the Combat chapter of the PHB and have altered my opinion (or should I say, my method of argument) as to what the proper RAW action is for a Sunder. This descrepency does not show in the SRD; it is much clearer in the PHB.
On page 139 the PHB defines "Melee Attack" as an attack, and thus as a standard action. From this point, references to "Melee Attack" should be understood as "Standard Action".
From here it can be clearly read that the table and the text are in harmony.
However:
Sunder, Grapple, Disarm, Trip, and Throw Splash Weapon all use the term "a melee attack" (or "ranged touch attack in the splash weapon's case").
Only Grapple strictly states, "If you get multiple attacks, you can attempt to start a grapple multiple times (at successively lower base attack bonuses)."
This reading would mean that Sunders, Trips, Splash Weapons, and Disarms are always and everywhere standard actions.
Unless:
Under "Multiple Attacks" on page 140 within the Standard Action section it says, "must use the full attack action ... in order to get more than one attack". This phrase allows that some actions that are usually Standard Actions may be used repeatedly with a Full Attack action. Specifically, mutlitple attacks, presumably including "melee attacks".
Under the Full Attack section it says, "If you get more than one attack per round because ... (list of possible reasons) ..., you must use a full attack action to get your additional attacks."
So the Full Attack action explicitly allows multiple melee attacks, though melee attacks are listed as Standard Actions. It would be a reasonable ruling that because Sunder (and similarly Disarm, Trip, Grapple and Throw Splash Weapon) uses a melee attack, and multiple melee attacks are allowed under the umbrella of the Full Attack, that Sunder maybe used multiple times in a round, and this is actually represented on the table: it is represented by Full Attack.
This would also mean that the description of Grapple being allowed multiple times in a round is redundant.
This reading allows:
- iterative attacks to be used as Sunders, Trips, Disarms, and Splash Weapons.
- the table and the text to be in harmony.
- my preference for characters sundering several times in a round
The alternative to this is to restrict all uses of Sunders, Trips, Disarms, and lobbings of Splash Weapons to Standard actions.
And I think both of those could be argued as RAW. At this point, personal prefence opens the door and makes a choice.