There are exceptions to every rule, and this situation is one of them. Texas is one of the few states that 8 point or better rules don't really work that well over all, other than a jumping off point for learning more. States like Pennsylvania, where the average age of bucks harvested is 1.5, is a perfect example of where point systems work well. One thing I always tell my clients, or people I'm hunting with, is the Fisherman Scenario, which goes back to education.
Deer management is just an extension of that way of thinking.
Let the little ones go, take more out of the middle, and keep a few big ones, or so it is in simple terms. Along the same lines, a lot of people know the difference between a black bass and a smallmouth, but can't tell a 2.5 year old deer from a 5.5 year old one. My grandfather used to tell me a story about a little town in Northern California where he lived. A guy pulled into the town cafe one day in a little red sports car and told everyone in the diner he was going mule deer hunting and asked directions to the public land. The guys at the cafe told him how to get there and told him to come back that night and show them what he got.