This is a technique used by Robert Bruce (?) I think for projection, which to me suggests it would work for WILD. I was doing this in the past and was able to get to a place of HH (just audio) with it. You might have more success.

@mimi: The idea is that you are just uncomfortable enough to not lose awareness. You arm falling will alert you that you're falling asleep. Eventually you would settle in for the WILD, but only after you feel you are close enough.