They said three major opportunities were missed during the treatment of Reid-Wentworth, known in the report as Mr Z.
The first was when he was first admitted to psychiatric services in August 2007, after assaulting two female strangers on the same day, with each occasion involving a weapon.
"The motivation underlying the assaults and the significance of his associated symptoms were never fully explored," the report says.
The second opportunity was when he was transferred to the rehabilitation and recovery unit after five months on the acute admission ward.
The report says: "Assessment of risk was incomplete and the potential seriousness of the two assaults on the women prior to admission was still not fully appreciated."
The third major opportunity was when he was readmitted to the acute mental health ward after the re-emergence of psychotic symptoms including thoughts of killing people.
"In addition, Mr Z had expressed dissatisfaction with his medication on a number of occasions and had asked to change it. The management plan at this stage contained no specific strategy to manage the increased level of risk of harm to others that Mr Z posed," the report says.
In addition to the three "pivotal points" where opportunities were missed, there was also little evidence of staff attempting to establish a relationship with his mother, who was a very important part of his future care plan, the report says.
"In spite of Mr Z's extensive periods of leave to his mother and older brother's addresses neither was approached for their views as to the success or otherwise of these arrangements."
Lewes Crown Court heard that Reid-Wentworth selected Miss Yates as his intended target after having fantasises about drinking the blood of an attractive young woman.
He then launched what judge Anthony Scott-Gall described as a "horrific and wholly irrational" attack on innocent Miss Yates in front of stunned shoppers, including children.
Prosecutor Rob Hall said Miss Yates was buying groceries because she and her boyfriend had just moved into a flat together.
He said: "Reid-Wentworth got off the bus and followed her into the store. The defendant followed her around the store for a few moments and then Miss Yates stopped for a while to look at the goods on offer.
"The defendant approached her from behind, put his basket down, took out a pocket knife of about nine inches and started stabbing Miss Yates repeatedly."
Reid-Wentworth went on to pin her down to the ground as he repeatedly plunged the blade into her, inflicting injuries to her face, chest, back and abdomen.
Shoppers, some of whom were young children, witnessed the attack and at first believed it was a joke between two people who knew each other.
But after it dawned on them that it was a real attack, some of the customers started throwing items including baskets at Reid-Wentworth to get him to stop.
