From what I have read slow cooling of aluminum allows minerals to precipitate out rather than remain in a more uniform suspension and or solution when you cast aluminum. This is why a cast aluminum part is usually not considered to be as good (and certainly not as strong) as a forged part where the metal is only heated up enough to be shaped by the press.
With that thought in mind would a process to rapidly cool the mold causing the aluminum to freeze off quicker make a better quality part? Maybe not as good as a forged part, but better than a slow cooled cast part? I am not sure where I am really going with this, but there are plastics that are injected into water jacketed molds for rapid cooling and freeze off. The differences in temperature for those plastics and water at cooling temperatures are much lower than that of aluminum and water, but the potential for a steam explosion in the event of a failure is still there.