Comparing algorithms (C) and (L)
If the input term and the abstract are written using the fewest number of parentheses and the abstract is produced by algorithm (L), then the same number of parentheses occur in the input term and the abstract. Turner's algorithm (C) usually introduces additional parentheses into the abstract. This makes it harder to manipulate and process the abstract. Even abstracting x from a simple term, like xyyyyyyy, illustrates this.
Compare the operation of (C) and (L) on your own examples to see how (L) preserves the structure of the input term, whereas (C) does not.
© Antoni Diller (28 May 2013)