Resolution:
ASSERTS are not sent through TutOut, so a developer cannot trap them by using TutSetOutputFunc. ASSERTS are sent to a fatal error file, which by default is stdout. However, you can redirect asserts to a different location by using the following function:
        T_BOOL TutSetFatalErrorFile(FILE *file);
There is also an accessor function:
        T_BOOL TutGetFatalErrorFile(FILE **file);

Please note that these function calls are not documented and may not be available in future releases.