Good to see things haven't slowed down in my absence!
Can you see that, by using the text under Weapons, and noting that the damage is because it's a weapon, I'm using the exact argument you're using for Flaming? Trip prevents the normal comparison of attack roll to AC yielding damage, but if it does not ignore the Flaming 'successful hit' language, how can it ignore the Weapons 'successful hit' language?
I never said that it didn't use identical language.
I'm asserting that resolving each attack depends upon a heirarchy of rules.
Trip, Grapple, etc, are all listed in a section called Special Attacks. Each particular subsection tells you whether or not an attack of this kind does damage, what the conditions are for doing damage, etc.
The rules for Magical enhancements do much the same in their own section- defining wether or not an enhancement activates or not, and what the effect of that enchantment does.
The problem is, the rules for special attacks and the rules for magical weapon enhancements are co-equal in the heirarchy, and there are no rules for giving precedence of one rules subset over the other, so one does not take precedence over the other.
Look at it like the military: You have your Commander in Chief, then you have a bunch of Generals, then Colonels, Liutenant Colonels, etc. If a General gives an order to a Liutenant Colonel under his direct command, that order is meant to be followed. If he gives the order to a Liutenant Colonel outside his direct command, that order is expected to be followed, but it may not be if it conflicts with the Lt. Colonel's orders from his direct superior. Orders between co-equals have virtually no force. At every level in the heirarchy, there is a bifurcation of chain of command.
Here, you have the general combat rule: Melee attacks do damage on a successful hit. Under that, you have 2 seperate rules sections, those dealing with special attacks, and those dealing with magic weapons. They are co-equal because they overlap and are not mutually exclusive- you can do special attacks with magical or non-magical weapons, and none of the DMG magical enchantments inherently affect special attacks. They are parallel because in one case it is the weapon doing (or not doing) the damage, in the other case, its the enchantments doing (or not doing) the damage.
In other words, while the Trip or Grapple section tells you what damage the weapon does and when, it tells you nothing about what magical enhancements do in that situation. And the Magic weapon sections tell you what the enchantments do and when, but not a word about special attacks (unless its something like a Sundering power that does both).
So, when the rules trigger at the same instant- here, the moment of the successful hit by a magic weapon during a trip special attack- you have 2 different operations going on: resolving weapon damage and resolving the effects of the magical weapon enhancement.
The result of which depends upon how YOU the DM decide to rule on how those effects are resolved: in
parallel or in
series, and
there are no RAW rules section to decide this.
In my campaigns, they are done in parallel, not in series. Thus, IMC, at the moment of the successful hit by a magic weapon during a trip special attack, one operation dictates that the special trip attack does no weapon damage, while the other operation dictates that the magical enchantments triggers.