IMO, Carruthers' skill level is far superior to the Carter Hargrave's of the world. Interesting sidenote, in the mid-60's, Bruce Lee visited George Dillman's dojo and he asked Dillman if he could spar with his best students. Dillman gave Bruce the thumbs up, but had to put a halt to the sparring sessions due to Bruce being "too physical" with his students.
In terms of Chuck Norris, it is important to note that for over 2 decades, Norris publicly denied ever sparring with Bruce Lee. A few years prior to Norris publicly admitting that he sparred with Bruce, Joe Lewis privately asked Chuck if he sparred with Bruce and Norris denied that they ever sparred. In addition, Bruce trained in grappling techniques BEFORE Chuck did, which included training with Gene Lebell, Wally Jay, and Hayward Nishioka.
Despite his training, Bruce was honest with himself and admitted to several students that, "my ground game is weak." Ergo, his obsession with footwork, closing the gap, and the use of the Hammer Principle. As Bob Bremer once said, "Anyone who had the nerve to face Bruce in the streets would have to go by the braille system."