Lessons I Learned Playing D&D Last Night

I. Pools are evil...

We see, at the fringe of our torchlight, a pool in a chamber.
Me: "I don't like rooms with pools in them; they can hide something big! Is anyone crazy enough to want to investigate this?"

II. If it looks like anything like a dragon assume it's a dragon...

Several deaths later, "yep...that serpentine, six-legged reptile was indeed a dragon!" At least the only non-henchman dead character belonged to the player that wanted to check out the pool...

III. Meta-gaming can always be justified

The DM was dangling a plot hook involving an island; Me: "Islands are trouble; there's always something dangerous on them. Small islands are worse as there's a higher ratio of danger to real estate."
The DM: "Hey...enough with the meta-gaming!"
Me: "My character just paid attention to the legends of Ulysses and Sinbad...he KNOW'S islands are BAD NEWS!"