I've only tried persussion to this point, have seen the leverage thing in use - it works wonders. Don't guess it matters to me how it's done as long as ya get desired result.
Robert: I would like to see picture of your holding technique when ya get time. I use a kinda spider hold myself - bi-face on leg, thumb and fore finger squeezing the base, two middle fingers on top, pinky at tip, all applying preassure toward the center of peice. Think I just need to do a better jop setting up the median ridge and get the angle right.