roll-it-up,
I haven't seen all of them, but i did enjoy tape #3 from san diego in 2003 "Infield Defense" by Van Horn of Arkansas. He's one of the best in regards to infield mechanics.
The Cal and Billy Ripken video is decent from '05, but focus' mainly on how they would play certain hitters (John Olerud sticks out in my mind) with a few good mechanical points. But the rest is interesting, but won't help a player unless they see their opponent numerous times in a season.
I haven't seen "Winning With Infield Play" from Chicago 2006, but hear great things about it.
And one video I will recomend for anyone in the game is "Coaching the Mental Game" by Ken Ravizza from San Diego 2003. Has nothing to do with infield defense, but is a must see.
Ravizza is a sports psychologist at Cal State Fullerton. I coached a few players from their national championship team in the Texas Collegiate League that year, and they said that his book, "Heads Up Baseball" as well as his numerous visits with the team, helped them recover from a 3-13? (don't quote me on that exact record, but it was bad) start to winning the world series. I recommend that book to all players, coaches, and fans of the game.
hope this helps.
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