WOW, I remember that because I used to have the video. It was Indurain and it was in a time trial. I can't remember which tour it was, but I'm gonna guess '94 or '95. In a book I read, it said that Armstrong couldn't get that experience off his mind and after the season he went to Indurain's home to ride with him and learn about his tempo technique. As big as he was, Indurain liked to use smaller gears and keep a higher tempo. Lance credited that technique with changing his ability to climb.
Yea, that was it.