From the very first page of Smiling Proud Wanderer at Lanny Lin's page:
I think it's sad that the first protagonist of the book, who was a kind young man with a heroic heart, ended up with a fate much worse than nearly any archvillain in Jin Yong's stories.Leading the pack was a beautiful horse, white as snow, with a silver bridle and stirrups. A young man in silk clothing, roughly eighteen years of age, sat on the horse, with a sword hanging from his belt and a bow strapped onto his back.
Xiao YuanShan, Murong Bo, Cheng Kun, Xie Xun, all have killed many more innocents than Lin Pingzhi did. Yet all of them ended up at the Shaolin Temple. Merely BEING at Shaolin means a chance for redemption, enlightenment and inner peace.
Even a full strength Ren Woxing couldn't escape from the prison beneath the lake without miraculous assistance from the outside. Was it really necessary for Ren Yin Yin to destroy all of LPZ's tendons? He was already blind, but she still insisted on turning him into a cripple like Yu Dainan.
Lin Pingzhi's most serious crime was killing his wife. But even she forgave him, citing his tragic past. Why can't Linghu Chong and Ren Yin Yin forgive LPZ and just send him to Shaolin? Linghu Chong had just received an extremely precious gift from Shaolin, namely the YJJ, which was the only way to save his life. I'm sure Fangzheng would have accepted to keep watch on LPZ, considering that all the negative karma caused by Bixie Sword Play originated in Shaolin in the first place, with their disciple Lin YuanTu scribbing it on his robe.
It would have been perfect for things to come full circle, with the last vestige of KHBD returning to Shaolin. The HSDS monks patiently recited scriptures during Xie Xun's inprisonment, and even he was moved and realized the error of his ways. XYS and MRB were given a clean slate and a chance to reach inner peace.
Cheng Kun, who committed a myriad more crimes than LPZ, lost all his inner power, was blinded, but he did not have his tendons destroyed. He did not become a cripple confined to a wheelchair like LPZ and YDN. Also, instead of being locked in a damp prison beneath a lake, alone, CK was still at Shaolin, where it's always possible for anyone to find inner peace.