great thread guys. I have always struggled with how best to measure this on snakey bows, or bows with uneven twist. These bows look like they have aligned handles when unstrung, but upon stringing the snakes and rollercoasters cause twist, which brings the string out of alignment. I basically use the "gravity" method (holding the string), and also pay attention to weather the belly lies exactly perpendicular to a line drawn from the string to the belly. In the end, if it shoots arrows well, it's good enough.