Comments on Chisanbop (Chisenbop) or Finger Math, Anyone?

Chisenbop is a method of computation using the fingers like an abacus.

Here's a tutorial.

www.cs.iupui.edu/~aharris/chis/chis.html

I think it was popular in the early 1980s, but fell out of favor.

There were a couple of books published:

The Complete Book of Chisanbop : Original Finger Calculation Method (ISBN: 0-442-27568-4)

Complete Book of Fingermath (ISBN-10: 0070376808)

Comments on the value or lack thereof?