Here is the problem. A leaner version of oneself in a picture always looks bigger and better, so he was leaner at the start so you guys are comparing pictures of a guy that is lean to a picture of him with an added 15 lb of fat and water, so it will not look as impressive. I suspect out of the 39 lb he gained 24 lb of muscle, now if he sheds those 15 lb you guy will realize that he did gain a lot after all.