I love this trick! I tested it in field and i have always gotten positive/playful responses from this routine (there is one exception: i tried it on a hired gun i.e. waitress). I use this routine after i run my opener. Check it out
http://www.youtube.com/watch?v=RR5Kfqr1uWQ
I usually care a bag of props with me. I have always carried the scarf on me as opposed to pulling it out of my prop bag. I feel that it would have to much of a 'try hard' effect if i would have pulled it out of my prop bag but then again i never field tested the scarf trick by pulling it out of my prop bag.
Cheers~