Jason Baldwin, 28, was sent there for further medical reports before sentencing after admitting the manslaughter of Maxine Boot, 37, on the grounds of diminished responsibility. The prosecution accepted his plea of not guilty to murdering her.
Baldwin - described as a psychotic loner with bizarre fixations - had taken an irrational dislike to the burger bar waitress who had a bed-sit in the block where he lived in Guildford, Surrey.
When they were alone in the premises on 10 March last year, he attacked her with a hatchet, sheath knife and pruning saw.
"It was a savage killing. She had severe head injuries and her throat was cut. She was then disembowelled with considerable professional skill in the course of the gruesome exercise after her death," Robert Seabrook QC, for the prosecution, said.
Baldwin then cut Miss Boot's body in half through the lower torso using the pruning saw to sever her spine. He had been sacked from his job at a local abattoir after attacking a work-mate earlier in the year, causing him grievous bodily harm. He became a dustman and made use of the black refuse sacks to wrap his victim's body before throwing it into a nearby pond, where police recovered the remains five days later.
The two halves of the body had been stuffed into bin bags bearing the initials of Guildford Borough Council and the number 28 printed on them. It was Baldwin's dustbin round number, and one with which he had a "bizarre fixation".
From medical reports - which described him as suffering from an extremely mixed personality disorder which suggested psychosis - Baldwin appeared to have decided to kill Miss Boot in advance and taken "some considerable pleasure from it".