At the bike shops, they tell him that he'll relax after a few hundred miles and get used to a longer reach (or lower angle). He doesn't want to! He wants a more upright position -- period. Our LBS has a fitter who is working with us and we're hoping he'll agree to his wishes.
I identify with your hubby's concerns, and felt the same way when I was riding my Trek 3900 mtb but thinking of maybe getting a road bike and drop bars. I didn't think I could handle the change in position and certainly didn't want to go hundreds of miles to find out if I could make the adjustment.
Then I got the Roubaix, and there was almost NO adjustment period. It took me a while to get used to the brifters, but in terms of my own comfort on the bike it was almost instant. Maybe one or two rides or so.
So I guess I'm saying there might be some truth in what the LBS guy says, and that it might not take as long. And I'm a guy who had terrible back problems years ago.