"I don't try it with other things. Alcohol is important enough to concentrate on," And the fact that he apparently had managed to develop a sort of 'booze sense' from all this managed to get another small smile from him, as he poured another drink.
"I haven't yet tried seeing if it can manipulate people," Which made it obvious by him saying, that Jack was safe. For now. He wouldn't poke around in people's brain and have them know, until he could control it, lest they end up like his stereo, a pile of silicon bits in the corner.