Are there advantages of transforming the layers into tables before putting the page online?

Not all browsers support layers so that's one reason, also if you have lots and lots of layers then the page can take forever to load which may put people off.
I know that pages are easier to set out using layers rather than tables but you can find ways round this.
I recently did a complete website using only layers (no tables) and when a professional web designer friend saw it he nearly fainted, so i have gone back and redesigned it using tables.

Dave