I'm glad he passed the MSF. Just know that he has only scratched the surface of training.
He needs practice. Not riding, but practice. Not getting on the bike and riding from home to a shop, restaurant, or scenic road, but practice. He needs to DEDICATE 1-2 hours a week in an empty parking lot working on the basics till they are second nature. Everything from stops, starts, foot placement, head turns, eye placement, braking, head turns, eye placement, balance, head turns, eye placement, friction zone, head turns, eye placement, throttle control, head turns eye placement, posture, and wrist positions. Did I mention head turns and eye placement? "Look where you want to go" must become more than words in a booklet or lecture.
He needs to get comfortable with the bike, not as in fit, but as in feel. That motorcycle is telling him things ALL the time, he needs to know what it is, and that comes with feel. What the engine, frame and tires are doing all comes with feel.
I apologize if I come across as gruff and on a soapbox, it's just that I have seen too many folks take one MSF class, and then think they are ready for the realities of the road. What they are really ready for is more practice.
Mark