Will be interesting to see what comes out after this. Being an F1 fan, I know just how hard designers work to circumvent the rules. For instance, it doesn't say how wide the deepest part can be. You could have a bat with 40mm edges, then chamfer the back so that it doesn't look like a continuation of the edge, but have a flat back 90ish mm wide, but 60mm deep across its width. Nowhere in the rules does it state a bat HAS to have a discernable spine.
Then of course, the complaints flood in that the bat looks awful and the rules are changed again and so on and so on........