Hmm, the GJ vs. YG debate has spawned a significant amount of discussion and thus questions on ZBT's invention. Is L/R Technique just all smoke with no fire? Is it just a bunch of tricks aimed at producing confusion? If so, then the entire wuxia world must be stupid because L/R Hand has existed for nearly 40 years from the time in was invented in LOCH to the end of ROCH and yet no one has been able to recognize that it's merely a ruse. AYF has seen it many times against GJ in LOCH due to their many encounters and how would a martial arts genius like him would not figure it out if the technique had no substance? The frequency with which GJ and ZBT use L/R Hand says something about its effectiveness in my opinion. Most unfortunate of all was the instance where GX cried foul and said it was unfair since YG only had one arm. ZBT should have used the 9Y Claw on her for interrupting the fight of the century.
From LOCH, GJ clearly says it yields an improvement in technique though there is not a gain in inner power, at least not one we can prove.. Noodles, I went over Ch. 17 of LOCH and didn't see any discussion of the inner power training with L/R Hand technique beyond what you have posted. However, that section does clearly state there's an improvement in technique.