Hmmm... well, have you ever heard the story about the young lady who was learning to cook a whole ham, and asked her mother why she was supposed to cut off the end of the ham bone? Her mother told her, "well, that's how my mama taught me to do it". So daughter and mother went to Grandma, and asked why she had always cut off the end of the ham bone before cooking her ham. She said that HER mother had taught her to do that, so they all three went to great-grandma's house and asker HER why she had taught Grandma to cut off the end of the ham bone before cooking the ham. Great-grandma said, "because my pan wasn't big enough and I had to cut off the end of the bone to make it fit."
My grandma who raised me, and her mother before her, always rinsed pork with vinegar before cooking - she said it was mainly for cleaning purposes, that it cut the surface blood and grease off the meat. I find also that it removes the slightly musty smell that pork often has when it first comes out of the cryovac. It also serves about the same purpose as a mustard slather as far as giving a wet surface for the rub to hang on to. I seem to be seeing a difference in smokering formation between meat with a wet surface and meat with a dry surface, so I'm playing with that as well.
Keri C, smokin' on Tulsa Time