GLAG,
I have to disagree with your comment, an IR is more useful than an ATPL which quite frankly he will not obtain later on in time. The IR improves your flying and RT skills and most importantly it can save your life! Knowing the convergency formula wont.
Obtaining the IR is more useful to have regarding flying wise, for knowledge then he can just read up on it, the jeppesen manuals are lying around the internet if you just search for them.