If what some people on this page of the topic have written is true, and the mind / soul does not disassociate from the body at death, then it could be that Hal's soul is currently locked up in his frozen brain and body, saying "FORGET IT!!!  THIS WAS A BAD IDEA!!! THIS WASN'T SUPPOSED TO WORK LIKE THIS!!! LET ME OUT!!! KILL ME KILL ME KILL ME KILL ME KILL ME..........."

I don't think anyone here wants to do him like that, do we?