It's really easy to glibly criticize someone else's design decisions when 1) you don't have a full understanding of their problem, architecture, or rationale for that architecture, and when 2) the medium of the conversation doesn't lend itself well to providing you a satisfactory explanation.

It seems as though you've gotten the tiniest glimpse of some details about the system and went on to assume he made a boneheaded decision and you know better. Do you have some secret evidence that he's incompetent and doesn't have a good reason for his decision?