I remember Pirate saying he short hopped with his nail, and Samus users scraped the X button.
I short hop with my full thumb when using Fox, and it always works for me... basically I'm wondering why other people move their thumb all the way to the right of the button... unless they scrape the bottom of Y or left of X I guess...
Post how you short hop with harder characters (just Fox, Samus, Pikachu, Sheik, ICs, Kirby and Pichu I think)