From someone who has trained in both Aikido and the ground arts I can honestly say that they are different tools to be used at different times. Its hard to compare Aiki arts with sport NHB contests. The mere fact that there is a ring, dictates how techniques are done. Sport venues mainly have prationers who work on their favorite things that work for them. Conversely, Aikido is an art, and there is more to it than just actual technique. I view things in ranges, kicking range-striking range, locking range-grappling range, and weapon range. When one is one the ground, one needs a ground art, as Shotokan said, same is true for a striking art, locking art etc. Aikido is an effective locking art, which is different than those ground or grappling arts. That is not to say an Aiki technique amy not work on the ground, but its not the best use for the tool. Its like driving a nail with a screw driver, it will work, but its not the best tool for the job. So I really think the comparisons are mute. When I learn a new locking technique, I relate it to my Aiki techniques, and work the variation based on the principles that Aikido teachs in its techniques. However, my 'spear' to the ground has no elements of Aiki to it, nor does my figure 4 leg choke. You are looking at fruit, but apples and pears in my opinion.