Nahh, I meant this stretch: @ around 3:10
http://www.youtube.com/watch?v=SE-yVP691SA&feature=relatedThose other stretches he shows in that vid you showed are nice too if you don't have space, don't have a band, or if you want to change it up. You can still do that stretch at 3:10 without a band though.
Yeah that groin stretch I like a lot, you can do that on the floor too if you don't have a nice soft bed or couch to put your leg on. You can even use lateral distraction on that too if you can.
For calf stretching this is what I prefer: @ around 1:15
http://www.youtube.com/watch?v=aLj_VkfQzJIAgain, you don't have to use a band, but it's always preferred. You can use a box like he does, or you can just use a wall. You should probably wear a shoe(make sure it's a low top) so the foot can grip on the wall.
About that Frank Yang video. He's strong, but his squat there is just atrocious. His knee wouldn't go in as much if he shoved his knees out first before descending to the bottom. Even if you have straight feet, you can still get a lot of valgus knee, but shoving you knees out WITH straight feet will get you the best results in terms of knee position/safety/power in my opinion.
You also have to consider that he's stopping at parallel so there are 2 things going wrong: 1) The bottom A2G recieving position, to get some soft tissue bounce(I say soft tissue because, you don't want to bounce on your ligaments or capsule alone, you should use a combination of muscle tension, muscle capsule, AND ligaments to receive load) 2) Stopping at parallel means the knees are at 90 degrees of flexion, which is the weakest position for the knee(the strongest being in full flexion, and full extension), so he reverses when his knee is at it's weakest point.
I'm not saying you have to use A2G when squatting for athletic performance, I'm just saying that A2G is nice when you want to squat and receive heavy loads(when trained right, it's actually easier going A2G)
For your alternating exercises shiz, I'll post later, on that board, I don't want this to look like another wall of text.
EDIT: Oh yeah, didn't see the stretching thing at the bottom, I'll post that hear, because it's more relevant.
Stretching for minutes is fine, as long as it's not like 10+ min. spent in one position. You should however, go on feel. You couldn't possibly performs all the stretches he talks about(on his mwod project he probably has a couple dozen) for a good quality 2 min. Everyday, and after your workouts(and even before you workout if you need the extra ROM) you should spend 10-15 minutes on stretching or soft tissue work. Pick 2-3 stretches and do them for 1-4 minutes each. Make sure you pick body parts that need more ROM or are getting real beat up. The rest of the time remaining can be for soft tissue work and stuff like that. Quality stretching(spending a couple minutes on what is bad), instead of quantity(stretching every muscle in the body everyday). Stretching should not be like exercising like you "just do it"(like a routine). It should be based on how you feel, and where your really banged up.