The Pattern: Given by Shahriar's answer, a pattern was found on the occurrences for the letter s.
A pattern of 2, 4, 2, 4, 2 in which each line follows this pattern for the number of instances in which the letter s appears.
The Double Standard: Tom's answer sums it up well.
Double s, you like doubles cluing double u (W), and there are 2U's so it's a W (doubles) story.
My Answer: I believe there is more to this than Tom and Shahriar have pointed out.
I believe your favorite letter is w and it occurs 2 times.
My Reasoning: There are a lot of things that add up to this, to include the answers that Tom and Shahriar gave. To top it off:
If you concatenate these numbers together, you get the number 24 which is representative of the letter w in the alphabet and it appears 2 times.
Also, following the pattern, there are two instances of w and they are both on lines where there are four instances of s.
Also, I would like to point out that the first occurrence of the letter w is also positioned at index 24 (1 based, including spaces and punctuation) within the passage; which, is either sheer coincidence, or pure genius.