Knockback still happens on every click when miningfatige is 126

Knockback still happens on every click when Mining Fatigue is a high number.

What I expected to happen was...:
The entity would not be hit unless the sword was done swinging.

What actually happened was...:
The entity gets knocked back on every click.

Steps to Reproduce:
1. Give yourself a high level om Mining Fatigue
2. Click rapidly on an entity
3. The entity is knocked back on every click, not waiting for the slow sword to "load".