We will primarily be looking at the over/under pass here. However to set it up we will be working to fold our partners legs so we will also briefly touch on that. As with the old timer pass we are addressing the legs first, and then passing the guard. We are using the leg fold as more of a set up to the over/under pass so we didn't get into a lot of detail with it Saturday. If I actually wanted to use this to pass my partners guard I would have to 1) address the ability of my partner to push my head away and 2) move my head under my partners chin, (where it is difficult to push away). Here Gavin is letting me do this by keeping his arms out of play.
For the purpose of class do not push on your partners head if you are playing guard. If you wish to try and reposition, push on the top of your partners shoulders and focus on moving your hips - not pushing your partner.
With the fold you can see that I have a hard time moving my partners framing leg. When I see this I don't try harder - if you can't move your partner.......... that's right, move yourself. I hold his knee stationary and move myself to the side then turn and bow into the side of my partners legs. Once his legs are flat I begin to walk around. Note that just like in the video your partners foot may still stick past your hips once you fold their legs. Be aware of it and lift your hips a bit allowing it to clear. The bottom person should be aware of it and do as Gavin does above - moves it out of the way.
A common defense to the above technique is for the bottom player to push out with their leg more when they see what you are up to. You can use this to secure the "under" grip of the over/under pass. With the over arm, (the arm going over your partners leg), you will want to move not just your arms but your hips. If when I secure the over grip I place my shoulder in my partners belly it becomes natural to line your hips up with your partners leg. Notice that I turn my hips the other direction. This makes it difficult for my partner to re-guard.
Once the staging position is obtained I walk my partner flat and then kick my trapped leg free. The over/under pass is a very solid pass. It works best when you set it up in a manner that surprises your partner because they don't see it coming. Efforts to dive into the pass typically end with you diving into a triangle. Over/under is another way of saying one arm in the guard and one arm out, which breaks one the basic rules of Jiu Jitsu. What prevents the triangle is covering the hips well by keeping your elbow tucked in tight and your partners knee under the knot on your belt. As I said above I like to put the hip of the over arm pointed at the ground. That helps you walk the right way and helps prevent the triangle.
All of these passes, (old timer and the two shown here), work well together. When passing half guard you can casually hang back and try to float your attacks between the three passes. One will eventually open and then it's up to gravity. In both playing half guard and passing don't try to rush the moves - get comfortable playing in the set ups so that it is difficult for your partner to read which technique you are trying.