[psandman]

I believe checking out is inappropriate, because it gives you no advantage and simultaeously may impact the game by giving information to others who are not entiotled to it.

For this reason it is certainly discourteous (AND WHEN A PLAYER DOES THIS I ALWAYS PRAY THAT THE REST OF THE HAND GETS CHECKED DOWN AND IT TURNS OUT HE WOULD HAVE WON OR CHOPPED). I hesitate to call it unethical generally, however it could be done unethically if you do it for the purpose of freeing up another player to bet without concern (say you have a friend in the game and your intention and you frequently check raise, you do throw away your hand because you want him to be able to bet without concern that you will check raise him -- here your motives make this unethical)

If I had my way, players who did this would be told not to and players who repeatedly did this would be uninvited from playing, but I'm not holding my breath to see this happen.