I notice the new 2005 compiler happily compiles my native projects, even ones that contain inline asm and variable param functions. It just warns me about the native code generated. The managed c++ compiler in 2003 could not handle this. So, why would I ever want to not compile with the /clr option?

I have found in the past that a mixed code application can spend 50-90% CPU time in mscorwks.dll even without a single managed class, just by adding or taking #pragma unmanaged/manged in some files. I am obviously trying to avoid this problem.