Griff paused for beer drinking, continued his story. "As he headed to a corner table, Dad passed a young woman with an open notebook spread out on the table in front of her. She had long black hair and a pretty profile, but that was not what he noticed. What stopped him at her table was a drawing of a skater making a jump and beside it velocity to jump calculations.
"This is very interesting." he said, "but the formulas you are using don't include all the variables."