I don't know what CDEV you're referring to, but what it's observing sounds like a distortion. Every UPP call into the OS looks like 68K code. This enables 68K a

I don't know what CDEV you're referring to, but what it's observing sounds like a distortion. Every UPP call into the OS looks like 68K code. This enables 68K apps to "just do it." There was always some sort of thunk to handle registers and calling convention, but by 8.5 and certainly by 9 the code on the other side was usually native. Certainly some calls were still 68K. That's why almost every OS call still needed to go through that song and dance. If all the CDEV did was see the border at the Mixed Mode Manager switch, the machine would indeed appear to be running 68K code most of the time except for those few generally non-UI PPC-specific APIs, even though it isn't (and I challenge you to spend a little time in MacsBug and see that this is true).