I switched a road/drop bar set up to a pair of Nitto All-Rounders (sort of a narrower version of the North Road) with new brake levers and such.
It wasn't cheap, but I absolutely love the frame and how well it fits, so it was worth it to me.
Take a look at all the pros and cons, write out an expense list (new bar, new stem, new brake levers, thumbies shifters, grips) and a labor estimate. Compare that to the $$ cost of switching to a completely different bike. Add in the value of bike-love. See what you come up with.
Meanwhile, get him to try some hybrids and see how they feel. That gives him a chance to both experience a different bike and test-ride different bars. I don't think I'd put more money into the Volpe until he has ridden a few other bikes/bars for comparison.
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson