A Blind Toss is a throw that starts with the dog being unable to see the disc, the human unable to see the dog or the target, or the dog and handler unable to see each other. A Blind Catch is the same concept but from the dog’s perspective.
Throws that spin in the same direction as the dog is moving will be visible to the dog. Throws that spin in the opposite direction of the dog will be blind.
Clock throws go clock, counter throws go counter. Opposite spins will be blind.
Two of the throws are Blind. Did you spot them? Here’s the lesson this video is cribbed from.