What started out as an exercise in aesthetics that had its origin in user feedback and suggestion has become a wonderful ABC/R variant. We don't do things for looks, we're actually moving away from what might be considered blings with shiny finishes (never had too many of these to begin with), and concentrating strictly on defense/duty oriented products.
While the original horizontal serrations on the ABC/R paddles are very effective (they're optimized to mitigate 12 o'clock to 6 o'clock movements), when the the finger's approach angle changes closer to 45 degrees and more, the horizontal serrations effectiveness is diminished.
ABC/R-AA has three different dimple sizes and depths, 30 dimples total. Symmetry is nice but in this case, doesn't serve us well. In order to maximize the large surface area of the original ABC/R design, we tastefully packed in as many dimples as possible, but not too many. Sometimes more isn't better, and bigger isn't better either. Placement and the shape of the object matter a great deal.
What the dimpled pattern offers is all around traction, regardless of the finger's position on the paddle, it is simply indifferent to the angles and directions of the finger's movement.
Credit for the dimpled paddles idea goes to the folks at Weapon Evolution. Thank you guys for encouraging us to do something different, which in turn compells us to break out and think outside of the norm. The dimpled paddles were somewhat challenging. It would have been easy to use a set of uniform dimple dimensions and simply blanket the paddle surface with it, but that would have been wasteful of the ample surface area the ABC/R design affords.
US patent D797,878 has been issued for the ABC/R-AA, Dimpled Bolt Catch on October 10, 2017.