Conclusion from the above: Sometimes grunting works and sometimes it doesn't. I use it as a last resort to stop a fast moving deer. Often, because of the noise they're making, they do not immediately know where the grunt came from, though they usually are more alert when stopped than if they just kept walking by. Sometimes they well jump the string when stopped like this, but more often than not, they will not. That being said, I usually take the moving shot if the deer isn't moving too fast and it is fairly close, 15 yards or in. The farther it is, the less likely I am to take the moving shot. And, of course, every now and then, they stop on their own -- but not for long during the rut.