It's poor form in my shop. There is not a good audit trail once you've invoked the interactive shell.

Like I said, if he's been given ability to do that (in which case it would have been set by the sysadmin), then he won't get a stern talking to.
That would be silly.
OTOH, I agree that for security reasons, you'd usually want to restrict sudo rights to cmds that don't allow that kind of access.