I started playing around with TI a year or so ago, but didn't really focus on the drills, so I wasn't doing anything correctly. When I started swimming again in January, I decided to do the 0 to 1650 program (which is 6-weeks long), and do one of the TI drills each week, either before or after my actual workout. I still didn't really get it until I watched the videos online, but I'm about to enter week 6 of 0 to 1650 (and drill 6 of TI), and my stroke is exponentially better than it was in January. For those of you who have the DVD, is it worth it?