Guys: Would you do this if you were "just friends" with a girl?

So there's this guy that I'm friends with, but we're still not quite in the "friend only" zone, and I have been getting tons of mixed signals that he likes me. (I like him.) We were at this summer camp, and they had a message board where campers could leave notes to each other. I was telling him how I wished someone would write me one, and said he would write me a note. The next day, there was one for me, and it said "I wrote you a note. Hello! PS: You're awesome. :-)" My friends all say that no matter how many mixed signals I get, the note means for sure he likes me. So guys: would you ever write a girl a note like that if you only thought of her as a friend?