You'd have inconsistencies because you'd need to block them over NFS
file systems where you can't lock down an inode in that way.
> You would also need a shell that ignores $IFS and such.
> You could call that a user space issue, or you could just
> completely clear the environment.
So you have a setuid wrapper like everyone else does nowdays - a secure
C program that therefore avoids the setuid script issue.