Then you are doing it badly. Dont say something is obvious if you suck at it. Plenty of people use it and never have an issue, i have never been called out on it.
I don't suck at it lol. And I'm not someone, maybe you, who thinks they are good at everything. I know what I can and can't do. I can do this. Almost anyone can master it in a week. Go show it to a group of teenagers in a high school and then tell me you didn't get caught, and even if they don't say something. I can almost guarantee you that they know how you did it. I've never been caught doing it on an "adult" usually someone around 20-30+. I don't why teenagers are more likely to figure it out. Just another problem... Most people in High School do not enjoy magic, they wanna see it to figure it out.
I love what Joel Paschall said in his BeLieVe video intro.
http://www.theory11.com/tricks/believe.php It starts at 0:59.
"The job of the artist is to convince the world of his lie"
Sometimes the job isn't good enough depending on who you perform too, no matter how skilled you are.