giving in?

Hawken talks. A lot. When he is awake he is either eating or talking. There is pretty much nothing else he loves to do more. He has recently discovered the power of "please" and now I find myself in a pickle... I can't tell if I am giving in or positively reinforcing him for using it. He will ask for something (usually something to eat, of course), and I am usually doing something else (aren't children good at waiting until you're busy to need something?) so I tell him, "wait just a minute". Then he follows me around saying "tease? tease? tease?" (his own personal version of "please") in the cutest, sweetest, but not so patient voice. So, he will wait the minute (asking please the whole time), and then I will give it to him. I used to say "thank you for saying please, that it so nice!" trying to get him to say that instead of "more! more!" or something else less polite than "please"... but now I don't know what to say. How do you explain to an almost 1 and 1/2 year old to only say something once and then be quiet? And how do I resist such a sweet little thing who is asking with such nice words? Really it wouldn't be a problem if he only said it a few times, but this little guy will really not stop until he gets what he is asking for and hearing "tease?" a million times in a row is head-ache worthy. :)