Referencing an .mdx within another .mdl?

Is it possible to edit an .mdl file (with notepad) and have it reference another .mdx?

For example, could you have an essentially empty pointer.mdl file, except that it references units/undead/necromancer.mdx. Thus, having a unit with "pointer.mdx" for Art - Model would display a Necromancer model in the game.

Further, if you can do that, could you have an .mdl that wasn't empty, but that referenced a "sword.mdx", allowing you to attach mdx's by referencing outside data instead of importing/merging geosets.

I assume "no", especially for the second example, or someone would have posted about it by now.

But... I've been thinking about it, and could find nothing in the forums saying no OR yes, so I had to ask.

Yes. You can attach models to models, both with options in World Editor, and with the model file itself.

Take a look at the Naga and Undead structures, they share a common birth model that is attached purely through the model file.

It's just a matter of adding an extra line to an attachment point;
Path "Units\Other\Bacon.MDL",
Gotta say MDL even if you mean MDX.
But I'm not sure why you think you need pointer files; why not just attach the other model directly in-game with a dummy ability of triggers?

Yes, I'm aware of the ways to attach a model using triggers (or buffs). The reason I was asking specifically about editing the .mdl is mainly curiosity. Recently I had idly wondered about 4 or 5 scenarios where having model "pointers" might be cool. As is often the case with any kind of pointer, the possible benefits have to do with memory useage, ease of modification across large groups, etc.

Things like: could you share the same basic birth effect between all the models in a set? Turns out, according to Whitehorn, Blizz does exactly this with Undead and Naga models. I haven't taken a look yet, but it makes sense.

I was also thinking about neat Shimmering Portal-like models... i.e. the purple-pink portal with 5 or 6 pink shadow-orb-like fragments around its perimeter. When I looked at that mdl, there were no references to outside files. But I wondered about whether someone COULD build the model that way, with one external shadow orb model, referenced multiple times.

Anyway, you get the idea. Just speculating. Thanks for the answers! If anyone knows where there's documentation about this kind of referencing, please let me know!

Yep, there's no reason why you couldn't do that with the portal. Would make it easier to change the orb, yes. Not a difficult job at all; just get the right pivots and parents for the attachment points and you're away.