It's the contrary, he refused to be weak anymore and shot the guy, the good weak guy would have made sure there was a trial but he shot him and then shot himself, the good guy. That's why he wouldn't show up at the restaurant were Susan was waiting, they were both already dead. Also the book is dedicated to Susan, as if she was dead.

No
One piece verbal symbolism is he expressed in his writing how devastating the word "weak" was. The story he wrote was about him redeeming himself after accepting his weakness. Even at the end the specific word "weak" was used before he finalized the deal with the suspect (trying to avoid spoilers)