It means training isn't his FIRST job. He does it on the side. More so, he probably does very little of it and rely's on the drugs/drug response to get himself on stage. Which by the way is still pretty fucking impressive. But not someone I would really give a shit about "training wise".
Being a PT is rarely more than a side job, if you're not Gunnar Peterson that is.
Getting a PT makes sense in two scenarios: You're a total noob and need guidance or you're a lazy fuck and need someone to push you and you don't have a training partner or don't want to wait and take turns during training.
Training is not rocket science, it doesn't even matter how you train, as long as it is consistent and you make progress of any sort. It's idiotic for an experienced lifter to pay for a PT.