a villain who unintentionally always does helpful things

A villain announces that he has poisoned the city’s water supply, but Commander Fistfight explains that the attack exposed neglected pipes and an embezzlement scheme involving security funds. Even the released pathogen has a nutritional benefit. The frustrated villain turns his weapon on the masked hero, only to cure his shoulder problem.

The ProZD fan wiki identifies the villain as Dr. Mean and groups these characters under Commander Fistfight vs. Dr. Mean; this is a fan collection name.