Found this video on youtube discussing defensive line play. The title of the video is Mack Brown - Defensive Line.
I'm wondering if this is actually Mack Brown, or someone has mislabeled the video. If this is indeed Mack, the last few years at texas have aged him incredibly, b/c this is a very young-looking Mack in the video.
Given that Mack's experience has always been on the offensive side of the ball, I'm not sure why he would be teaching defensive line techniques. He has never coached on the defensive side of the ball, going all the way back to his time as a WR coach as a student coach at Florida State. He was a WR coach, a QB coach, and an offensive coordinator before becoming a head coach. While I can see using Mack's name to sell videos, I don't see why you would have him actually demonstrate the defensive line techniques himself.
I am led to believe this is some other coach, but I'm not sure who. The video itself appears to have been taken in 1998, given the publish date on youtube, and the inclusion of the Heisman Trophy video at the end of the video.
In any case, it is a good video to teach basic defensive line techniques.
Here is the video: