Never felt the need to exploit it.
Try exporting a cube with a few subdivisions on it and see how far you go, adding more subdivions until you get an error.
I did read somewhere that the physics proxy needs to be under 10k tris, again never tried this and 10ktris is a lot for a physics proxy.
64k is the maximum number of vertices. I don't think it cares how many triangles or polys you have as such, just the verts. Ark is correct, the limitation is enforced by the exporter, so no cgf objects (brushes or entities) can be larger than that.
Either way, if your mesh is that big, you probably need to look into splitting it as has already been suggested.
Replies
Try exporting a cube with a few subdivisions on it and see how far you go, adding more subdivions until you get an error.
I did read somewhere that the physics proxy needs to be under 10k tris, again never tried this and 10ktris is a lot for a physics proxy.
Don't know what your trying to export that needs that many tris, if it's a large mesh, you'll wanna split it up for occlusion reasons anyways.
Either way, if your mesh is that big, you probably need to look into splitting it as has already been suggested.