Looking more closely on the use of str.scan vs str.chars.each_slice
string slicing, it appears that the best one to use depends on what
form of slice one needs.

If I need a string yielded that is a substring (a slice) vs. an array
of characters or array of bytes, then the scan method is consistently
faster on my machine.  However, if I want an array of characters or
bytes, then str.chars.each_slice or str.bytes.each_slice is faster.

Most of the time for me, however, I need a substring slice.

Aaron out.