There is a comparison of SS between Patrick Chan and Yuzuru Hanyu here: http://the-real-xmonster.tumblr.com/post/165539440729/i-have-heard-people-say-that-yuzurus-and
However, I haven't really found anything I would call an unbiased comparison between the SS of Boyang, Nathan, and Shoma. I know there exists a disparity between them, and I know they each have their own strengths in other sections of PCS (Boyang has generally better PE; Shoma is generally better at IN), but I want to know how to compare them. I also want to know what facets factor in: Is posture something that affects SS? In general, how do you determine who has good SS, when it's not extremely obvious like with Carolina Kostner?