If I'm reading the information right for Algorithm::Diff it will not return what I want. LCS appears to use a "distance" measure. That is it determines the distance over which two strings have the most information in common. This is done by computing hits and misses. The maximum hit count will give the longest distance over which the two strings share commonality. Usually these types of algorithms have a penalty for misses. Nonetheless as I understand LCS, if we are using the strings "banana is split" and "bananas split" we can line up the strings a couple of ways.

banana is split
bananas split
banana--s # 7 characters in common and two misses "-"

or

banana is split
  bananas split
   ana--s split # 10 characters in common and two misses
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Allowing the strings to flex by putting holes in the strings we get...

banana is split
banana..s split # 13 characters in common and two "holes"
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...by putting two holes between "a" and "s" in "bananas"

So "bananas split" (removing the holes from "banana..s split") would be the result of LCS, but I want "s split" with a hit count of 7, no misses and no holes.