In this Dune 2 speedrun, the player builds sonic tanks and sends them to destroy the enemy base. Before sending each tank, he exposes it to friendly fire until it gets a certain amount of damage. He even has a dedicated regular tank whose sole "mission" is to shoot own sonic tanks before sending them to battle.
What benefit does this give?
Below is a link to the video with a timestamp. He explains this earlier in the video, but the sound quality is so bad it's completely unintelligible.