I think that concise is always better than the alternative when it comes to core rules. These are games and people should be able to understand them and get playing as fast and as successfully as possible.For more info, consult the 5000 page Guide to Forgotten Realms.
I don't understand the fascination with explaining things with as few words as possible. I guess it would be useful though in a core book either full of full page art or one with 50 other species in it.
Your setting tomes for D&D can -- and should -- be chock full of lore! That is what setting books are good for.