Better recovery would make grievous injury more dangerous for the assailant, not less. Leaving aside murderous intent for a moment, and think about a car accide

Better recovery would make grievous injury more dangerous for the assailant, not less. Leaving aside murderous intent for a moment, and think about a car accident from reckless driving: the party at fault would be on the hook for the bill, and regrowing complex organs won't be cheap.