Interesting. My girl understood the behavior quickly, so I phased out the targets. But then she started to slow down, so I added double targets back in (one at the bottom for the nose touch, and one farther out as a reward for the quick release) and that really increased her speed. Now we almost never use them, but I do see myself bringing them back out in the future to increase speed if necessary.
Hmm, never thought about a double target. Quite interesting!