Liberating Command spell from Andoran sourcebook

[Quandary]

The spell states "If the target is bound, grappled, or otherwise restrained, he may make an Escape Artist check to escape as an immediate action. He gains a competence bonus on this check equal to twice your caster level (maximum +20)."

"Officially", does that mean you can ONLY make an escape artist skill check and NOT a CMB check to escape? It seems like the two approaches (skill/CMB) are intended to be interchangeable and used depending on the would-be-escaper's strengths (skills+DEX/BAB+STR). I know I would house-rule that it applies to/allows CMB checks to escape grapple as well, but it'd be nice to know the "Official" ruling here.

[azhrei_fje]

Looks pretty clear to me that it means Escape Artist only. Otherwise it would've been worded to allow the bonus to "any of your CMB checks" or "as a bonus to your CMD".

[Quandary]

I guess my question is as much about the core rules themself, and whether or not escape artist / CMB to escape are supposed to be interchangeable, and if this spell should possibly be errata'd to better reflect that. I mean, if they ARE interchangeable this specific spell wording could be superseded by the general interchangeability, though clearer wording would be better in that case. Which is as much an issue of official design intent... So any word from Jason on this would be cool.

[azhrei_fje]

Quandary wrote:

[...] and whether or not escape artist / CMB to escape are supposed to be interchangeable [...]

Why would you think that? I just read through the grappling section again and I see nothing that would even remotely suggest to me that they are the same. After all, one you can spend skill points on while the other goes up at a rate based solely on your BAB (if we're talking about E.A. vs. CMB).