"On the other hand, there are many schools which come out in the lower half of the league tables which are performing magnificently and do not get recognition for it, far less encouragement.
"All of this was going to be exposed by the value-added approach."
Ronnie Smith, general secretary of the Educational Institute of Scotland, who was a member of Mr Wilson's action group on standards, said that the union continued to believe that raw exam results are "meaningless".
"We shouldn't devise an assessment regime to make judgments about the purported effectiveness of a school when what we need is to know the impact a school makes on its pupils. That would suggest a more sophisticated analysis which value-added approaches represent."
Fraser Sanderson, president of the Association of Directors of Education, said that a lot of work had already been done by local authorities on value-added approaches and "we should now concentrate on that".
"There are many schools doing excellent work and not getting the credit for it, which leads to them losing pupils as a result," Mr Sanderson said.