Wow. That dog is super duper fast. Wow. I'm kinda speechless. How do you even keep up with a dog that fast? LOL. Great runs and yay that he can jump 16" now. I know although Koji can clear 20" pretty easily, I'd rather jump 16" too.
My two cents....and I know this isn't going to be easy to fix.....I saw that your FCs are a bit late (with that speed, I doubt I'd be able to do any FCs). You are doing a lot of RCs (to be expected), just make sure he reads you correctly. I kept watching the one where he went into the tunnel wrong, over and over again. You were lining up correctly. My two thoughts was 1. it looked like he was on that path already to the left end and 2. one arm was pointing to the right, one arm was pointing to the left.
I can't do the left/right either. Anything anyone thought of is basically me having to "translate" it in my head. i.e. the clock thing, yeah, I'd have to actually think about numbers then left/right. Wouldn't work. Using replacement words, like turn and spin, I'd have to think, "turn was for left, I think, and left is right, right?" lol. So....I've learned this instead. I say "here" if I want him to take an obstacle nearest me (discriminations or ends of tunnels), and "out" for going away from me. I also started working on using "switch" for him to turn the opposite direction he's already heading, so he knows to turn. People use all kinds of things, but for me, this works. Here (near me) is natural. Switch is me telling him to switch directions.
Just thinking out loud....for that tunnel, you would've needed to push him out to the tunnel. I've seen ExA/B ppl do a RC to lead the dog a different direction. i.e. since you were behind him, you would've have done a slight RC behind him between the two jumps prior to the tunnel. I know it's weird and I can't say its' right, it's just what I've seen ppl do. I thought it was strange, until I realized it was to help the dog "switch" directions a bit, even if they didn't need to full blown turn that way. I hope that made sense.
Like I said to corbinam earlier in my thread, I can spot things other ppl do, but it's so hard to "see" it myself when I'm running. I even think I'm doing things differently, until ppl tell me I'm not, lol. So take what I say with a grain of salt.