Inappropriately Sized Weapons & CMB

[K-kun the Insane]

Do the penalties from inappropriately sized weapons apply to CMB rolls with the weapon?

I'm thinking of having a Medium character wield a Huge Swordbreaker Dagger. That's -4 to hit before Proficiency and BAB and STR which isn't great, but is doable with a full BAB class like Barbarian. The weapon itself gives +4 on disarm and sunder attempts against bladed weapons. Would the fact that it is Huge make it a net +0 before other modifiers?

[Chess Pwn]

yes

[DM_Blake]

Yep.

You apply all bonuses and penalties that affect your attack rolls to your CMB rolls.

So in effect, you're taking the -4 on all normal attacks you make with that dagger and getting no benefit on the CMB checks. It does a d8 damage, but you could just wield a longsword in one hand to do the same damage with no attack penalties and anything you want in your free hand, or just wield a greatsword in two hands for more damage and no attack penalties - in all three cases, your CMB rolls would be the same, but the two swords have other advantages.

[K-kun the Insane]

I'm looking for an interesting weapon to pull an Amiri with, I thought the idea of a huge dagger that helped with disarming and sundering would be good, but the CMB penalty removes it's usefulness.

Unless the Disarm and Sunder weapon features stack with the dagger's text? It says it's a Disarm weapon and a Sunder weapon, so +2 to those even if you're not proficient. If you're proficient with the weapon you get a +4 vs bladed weapons. Would that be +4(+0) or +6(+2) vs bladed weapons and +2(-2) vs other weapons?

Anyway, any other suggestions for Amiri-sized weapons?

[Kazaan]

Arguably, the two parts are separate. It has the Disarm special weapon property and a "see text" property which forwards to the "if you are proficient..." part. They aren't of the same type, thus, without further data, I'd say they stack as it stands. But keep in mind that it might be clarified that both the bonuses come from the "same source" (special properties of the weapon). But, thus far, there is no prescient for all the weapon properties put together to be counted as a single source.