I suppose, but even then he would have to take time to review the state of the puzzle. You would still expect him to take longer to spot complex details, and perhaps he'd examine a piece or two to refresh his memory.

But that isn't my true rejection here.

If you assume that Claude's brother "spent arbitrarily much time" beforehand, the moral of the story becomes significantly less helpful: "If you're having trouble, spend an arbitrarily large amount of time working on the problem."