But there is no real difference between your idea and what is currently in place in cricket games. Trying to bowl faster doesn't automatically mean that you pitch it fuller. Also, the no ball idea in the middle of the bar is not intuitive, and nor does it represent the nuances of bowling very well. It's just not a risk you run in real life (missing normal and bowling a no ball). You generally just fall slightly off target.
In real, mostly no-ball happen accidentally. Something we can't predict when will happen. That accidental nature is not there in the current speedometer and the one suggested by you. I think a very small no-ball section at the middle will some what bring this accidental nature to the game.Also with no-ball meter suggested by you, we need a separate meter for speed.
I didn't say trying to bowl faster automatically mean that you pitch it fuller. But what I did said was, if you are trying to bowl a good length ball as fast as possible, there is chance that the ball will be more fuller and ended up as a slightly fuller length ball than the bowler intended if his accuracy stats are low. Like that if you are trying to ball in the lower end of the good length zone very fast, there is a chance that you end up bowling a shorter ball than you intended if accuracy is low. If the bowler has Mcgrath's or Joel Garner's accuracy stats, then he can pitch the ball any where he wanted with the maximum speed possible for him. In both case case of trying to ball faster and trying to bowl slower, bowler will depart from his natural rythm (you understand it if you are a bowler) and it really affect a bowlers accuracy.
For a low accuracy bowler if he needs to bowl a perfect ball he needs to bowl at his normal speed(there fore no change in his bowling rythm). As far as I know speed variations in current TAOC is a very good tactic to fool batsman and it really makes batting harder. Then why don't make bowling also a little bit harder. Currently it is a piece of cake to bowl slow ,fast or normal balls, so bowler can run all over batsman by speed and delivery variations and there is no risk for a bowler while try to bowl a fast, slow or normal delivery. By introducing no-balls zones for fast,slow and normal deliveries the bowler also need to bowl very carefully and in addition to the no-ball zones speed determines accuracy also bring some difficulty for the bowler.
I'm also not sure about no-ball zone at the middle idea, but I think it will bring some accidentality in to bowling no-balls.
Another idea is to increase or decrease the size of the no-ball zones according to accuracy or some other stats of the bowler. That is smaller no-ball zones for great bowlers or larger no-ball zones for part-timers(so they need to bowl more carefully).
I don't know a perfect solution for no-balls, but this is closest one that I know.
Any other good suggestions or ideas are welcome.
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