When I was a lad I was quite versatile with the swami. I can write with both hands, with thumb or forefinger, quite legibly, numbers, words and sentences. I taught a workshop on its use when I was a member of the PEA, available on my Secret Writing DVD. I used it for about twenty five years, I suppose, and will occasionally show off with it when I hang out with mentalists (rarely these days). I've told people for years that it takes months, sometimes years, of practice to fully master the swami. A lot of people seem to think it's easy to learn to write with a single digit, without looking at the writing. If people put in as much practice with a swami as they do with say, a double-lift, they would produce perfect Spencer penmanship.
Far be it from me to disagree with an authority such as Barefoot Boy, but I abandoned its use several years ago in favor of other techniques that I developed that accomplish similar ends. Some of these techniques appear scattered in my writings; others will appear in Gods With Feet of Clay Volume V: Secreter Writing (shameless plug). Still others are in my vault of "Dirty Tricks I Keep Between Myself and Alain Nu." :p