The mention of BTL might mean that somebody in the department had a chip habit. Lots of deckers used chips for recreation, but most knew enough to stay away from BTL. The implication that a decker was involved in the dangerous pastime could get him a black mark in his record that would affect the promotion schedule. Justifiably. No legitimate corporation wanted to trust its Matrix secrets to someone who was an addict. There were too many cases of black-mailed deckers stealing files, or crazed Matrix runners crashing systems when their delusions crossed over into the already hallucinatory reality of the Matrix. A decker who chipped would likely be canned and blackballed.