Behavior Adjustment Training ( BAT) with my Fear Aggressive dog, Arnold

I am not a trainer, but have been working with my fearful dog Arnold who is also reactive to other dogs. He tends to snarl, lunge, and growl at other unknown dogs. I adopted him from a local rescue 3 months ago after he had been in foster care for 14 months. This is our second BAT setup. The overall length was about 35 minutes, but it has been pared down in this video. I filmed this for myself. And interestingly, one of the main things I learned from watching it was that what I thought was a slow st