There's a bug with gatling guns in the game that cause them to spawn projectiles at the position they were one frame ago. Keen literally refused to fix it, stating that it's "not a bug". What this script does is allows you to offset a piston one frame ahead to where it will be, and place a gatling gun on it to counter this issue.

I guess you'd use this for a piston-based suspension, if I'm reading everything correctly?