As further evidence for you I've been formally diagnosed with carpal tunnel and ulnar tunnel from sports when I was younger and over a decade working in front of computer. Hand swelling, total numbness, etc. After starting the armstrong pullup program ages ago now I noticed I didn't really have as many issues (it was actually mostly gone except when the weather aggravates it). The hanging in tension is the key here I think. The nerves running through your elbow and wrist are very particular about positioning and I wonder if that does something to "realign" them via muscular development.