I appreciate the compliment, but I don't consider myself a Professional, but I do understand what you are saying. Although when the time comes when he is ready to purchase a lens I would still lean towards the L. It's just a better investment. It won't depreciate like other glass, and it will well outlast others. Plus when he is a race car driver he can have his "wife" use it to take professional quality shots of him with it on the track for sponsorships and such ;)
Same 3 lenses I have for under $2k.
70-200 2.8L
17-40 4L
10-22 3.5/4.5 better option for wide angle on a crop body
50 1.8