There was one time in Nexus (i think b2? awhile ago) where i needed to nobuild some big areas, and I used func_nobuilds. These were horrible. Players running on them felt that they were lagging or sticking to the ground a bit, and aliens couldnt drop structures on them either. I eventually fixed the map up so that I could reduce the nobuild areas by about 90%.
But there still is that remaining 10%, and I've recently come across a perfect example of using the alternative; the nobuild texture. But I'm wondering how to use it. Do you place a func_illusionary, 1 unit high, covering the ground of the area?
The mapper of Ns_Titan did this in response to an issue we found, and I was surprised to find that it worked so well, so now im interested (and he hasnt gotten back to me yet

). I can't fathom why one would really ever use func_nobuild over this texture method.
Any help?