I can't think of any reason not to. He might get a bit stubborn and not want to eat without the canned, but don't cave! He won't starve himself 
I don't know how often you take Gemma out but I live 25 Km. to the nearest town basicly I live in the booniesI did that with Gemma a few weeks ago. She was stubborn to eat at first but once she finally got hungry enough, she ate. She now gets water-moistened kibble three times a day, but I might just cut down to two soon with a few snacks mid-day because she rarely eats her lunch anyways.