FWIW, the Texas CHL requirement is shooting at 3, 7, and 15 yards.
Equally important is training with different techniques, positions, lighting, etc.
Additionally the Texas CHL is timed:
3 yard line - 20 shots:
1 shot in 2 seconds, 5 times
2 shots in 3 seconds, 5 times
5 shots in 10 seconds, once
7 yard line - 20 shots:
5 shots in 10 seconds, once
1 shot in 3 seconds, 5 times
2 shots in 4 seconds, once
3 shots in 6 seconds, once
5 shots in 15 seconds, once
15 yard line - 10 shots:
2 shots in 6 seconds, once
3 shots in 9 seconds, once
5 shots in 15 seconds, once
You'd be surprised on how many folks have a tendency to get the jitters on the firing line thinking about the seconds rather than the target.