Noone said you're intermediate, neither did I. I just said it happens so often that people have a mod idea, and ask others to join them. Instead of starting to make content themself, showing it's not just an impulsive action.
I'm talking from experience, most mods don't make it. I joined up with two others a long time ago too. Our mod failed, just like the many. Don't underestimate it. But you're free to try and if it works, that's just great. If it doesn't work, well, you learnt something too...
I do some modeling, it's not so hard once you get the grasp of it. Some persons get it within a few weeks, others need months. Anyway, creating a mesh isn't that difficult after all. Skinning can be little harder to get right, and finally animating is the hardest part. Creating realistic animations, that is. Anyway, a model can easily be remodeled without having to change the animations. Only when the skeleton is modified, you'll need to reanimate the model.
I'm also doing some coding, albeit very basic still. It's not that hard to get a little understanding of C++. With basic C++ knowledge, one can make nice adjustments to the code. For the more complex additions, you'll need to have some more insight though.
Personally, I think it's very usefull to have at least a little knowledge of every area of game-design. Especially mod leaders might find it very usefull. You'll learn things are not just 'for some reason' acting like they do, but you'll see what goes on behind it. And with some effort you can turn it just the way you want. You'll also have a better oversight of what you can and can't do for your mod, and how many time and effort is needed.