Judge Joyce said the content of an affidavit by Mr Duff about his literacy problems sat comfortably with the evidence given by Literacy Wairarapa, which made it plain that at the time he was held to have vocational independence in the two clerical positions, Mr Duff had "no prospects at all of actually doing that type of work".
Literacy Wairarapa has however been credited by Mr Duff for bringing his level of reading up to the stage where he could read the court judgment.
At the time he was injured, Mr Duff was working as an electrical linesman with Rural Power, and has not worked since the crash.
Judge Joyce said reports showed when jobs were discussed with Mr Duff he "generally exhibited a constructive approach, one manifest in comments that were thoughtful and positive rather than troublingly negative".
In 2008 he took part in several training courses related to the electrical industry and lines transmission work and in March 2009 a specialist in occupational medicine identified work types in which "medically speaking" Mr Duff should have the capacity to work for 35 hours or more a week.
These were long-haul truck driver, excavator operator, forklift driver, warehouse administrator and electrical cost clerk.
But 18 months later a doctor engaged by ACC as a medical assessor concluded Mr Duff had major mobility problems.
"He uses two sticks to coincide with his right foot fall.
"He does manage to walk in this manner but is somewhat slow walking and he sometimes uses a wheelchair at home."
The doctor reported Mr Duff had difficulty with balance and "gets soreness in his left knee, both hips and his back".
"He can get a sore left foot and tends not to go out on rainy days as he doesn't feel particularly stable and can slip quite readily." Mr Duff's' job capacity fell to 30 hours or more a week only as a stock clerk or warehouse administrator, the doctor said.
In the middle of last year an occupational physician reported to Ms Angus-Burney that Mr Duff was "substantially illiterate".
He could drive by steering with his left hand and using the accelerator and brake with his left foot and apparently on that basis was sent for work trials as a road roller driver and a forklift driver.
Those in charge of the work trials refused to teach Mr Duff, considering him to be a health and safety risk.
Mr Duff had never used a computer, and after 13 one-hour lessons did not consider he had "anywhere near mastered the use of it".
The report said Mr Duff "probably could never have learned to use a computer" but the two job types that remained to him would have meant "a good part of the time would be spent sitting at the computer or performing clerical tasks".
Judge Joyce said ACC needed to "seriously consider" establishing a means of effectively screening people whom it intended to put through computer training "so as to identify whether they are up to that without need of some level of literacy enhancement education".
He said it was "troubling" Mr Duff was at risk of being put into a job on account of a "misleading" CV prepared by ACC.
Mr Duff affirmed he had not worked since the crash. He had volunteered to return to Rural Power and, in fact, had been invited back but there was no real work for him.
Sometimes he would sweep the floor but, as he was still on crutches, this could only be done slowly with a broom and when a new company took over he could not continue as he was a "health and safety risk".
Allowing Mr Duff's appeal, the judge set aside ACC's September 10, 2010 determination of vocational independence and said ACC must restore to Mr Duff the entitlements of which he had been bereft.
