| Tangrid |
Oh, so many points to make.
First, I realize this thread is a little old, but while looking for people who actually cite authority (thanks by the way), I found some ridiculous arguments.
As for the distinction between a carried inanimate object (which acts as part of your person for most purposes) and a carried animate object (grappling or mounts), I don't see how people can be so confused. The rules are very different for attended objects and carrying/grappling living things. The one "gray area" regarding portable holes and bags of holding is actually a red herring. You can put people/things in a bag of holding (which acts as a portal to an extradimensional space), and then carry the bag of holding (an inanimate object without any living thing inside of it unless a body part's poking through) via Earth Glide as an object. This is not the same as putting a halfling in a chest, because he'd still physically be in the chest.
With regard to how Earth Glide works, it's really quite clear from the ability description. While the DM can always opt to override the rules (at his/her peril), the fact that it leaves no trace of passage and is undetectable means that the earth isn't actually being displaced. The argument that this just means you can't detect it from the surface, so long as it's sufficiently underground is reading WAY too much into a fairly simple description. Some DMs would apply logic and say that only things similar in construction to the elemental could travel this way, but that's not necessary.
The description of "moving as easily through the earth as a fish moves through water" could very well be construed to mean that the medium (earth or stone) becomes fluid immediately around the elemental, closing seamlessly behind it. This would allow more flexibility for who/what can be carried. If you gave adequate warning to your players of how your version of Earth Glide works, leaving them partially entombed in stone could provide an interesting dynamic. If you wanted to kill them in an entirely unfair way, you could bury them a mile below the surface in a perfectly-fitting tomb of stone. To actually be fair about it, why not apply the mechanic that says you take damage and are shifted back to the point of entry when your Earth Glide effect ends (it ends when you're no longer in contact with the grantor), as the spell? This allows your elementals to make full use of the ability, without providing an "instant" or "very-slightly-delayed" death attack.
If you go with the "only carried objects" approach, this is nothing like water or air. With this approach, you simply can't bring other animate things along with you. Period. If you go with the "earth parts like water" (for the user) approach, then the grapple bonus for moving into harmful terrain is the least you can do.
Finally, the idea that this in any way resembles the incorporeal trait is so far beyond logic it's hard to address. Incorporeal objects don't have a special affinity with any "real" thing the way an elemental does. They don't coexist with the wall or floor, they just ignore it. The notion that you could grant the incorporeal trait to a physical creature is laughable. Incorporeals have trouble affecting the physical world AT ALL. They wouldn't be able to bring things along with them except in very rare circumstances (a wizard's or druid's familiar/companion, which gets share spells, for instance).
See above for why you don't need to include your familiar as a creature for purposes of spells like teleport.