He's right. Not only would your first idea be unorganized and turn into a HUGE mess after time went on, but it would require more of a server load to close the first database connection and open it up again to get into the separate db. The separate table method is time tested and is quite probably the best and most efficient way to do it.
"Give me the place to stand, and I shall move the earth" - Archimedes
"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts." - Bertrand Russell