Something that irritates the snot out of me is this idea that a dragon's horde is just it's triple standard treasure. Such does not a horde make. It's triple treasure is probably just what it has on it at most times, because a dragon's "horde" should definitely be its own adventure and significantly more than than simply equivalent to killing three common enemies or 1.5 NPC-classed enemies.
I think I'm with you, but just to be sure.. . In other words, what I like to do when planning treasure (ie hoard), i'll factor in WBL for say the entire 2 to 4 levels of an adventure I'm planning. I'll then spread around the treasure accordingly, so the hyena pack encountered outside the blue dragons lair may have been an equivalent challenge, but all the coins are sitting inside the dragons cave. I'm simplifying, but is that the gist?