Many teachers surveyed for an evaluation of the pilot qualification said they had seen a turnaround in students' confidence and presentation skills, and that it nurtured better team workers. But parents of bac students are still highly sceptical, with a fifth of those surveyed totally against it.
Experts from Nottingham university found pupils were "neutral" rather than "enthusiastic" about the bac, with many questioning the relevance of some elements of the core programme. Views from teachers, parents and pupils have been put together for the first time since the pilot advanced-level qualification was launched three years ago.
Evaluators received written responses from 134 teachers representing 21 of the 35 national pilot sites. They also conducted interviews in 11 schools and nine colleges, where a further 115 teachers and 156 students were quizzed.
Responses were more positive from teaching staff at schools, with gripes over increased workload and administration topping concerns rather than course content. Last year, college students were twice as likely to fail the new qualification than school sixth-formers, with just over a third of Wales's first bac cohort gaining the advanced diploma.
But the survey showed college students were more confident of completing their courses, and of gaining employment or training. In all, returns were collected from 1,880 students - including three who had dropped out.
Advanced bac students study a core and options. The core has three parts, including Wales, europe and the world, word-related education, and PSE.
Candidates have also to complete an individual investigation. Students must achieve six key skills. The core certificate, combined with the options of A-levels or equivalent vocational qualifications, forms the diploma.
The bac diploma is worth an A-grade A-level, or 120 UCAS points for university entrance. Overall, pupils liked the language module, with 41 per cent saying they would take it if it was optional. But teachers would drop it, because they thought the 20 hours timetabled for the module was too little. A majority of Welsh bac students would not opt to take the Wales, Europe and the world programme, if given a choice, the evaluation survey revealed.
All groups favoured the bac's emphasis on key skills, including 70 per cent of parents. But teachers wanted to lessen advanced students' workload by allowing those who have already gained a C-grade GCSE in, for example, maths, to be excused from the numeracy skills module.
More parents of school sixth- formers (65 per cent) responded to the survey than of college students (35 per cent). Parents' biggest concerns were about whether employers and universities would accept the bac (20 per cent), followed by their children being prevented from taking four A-levels. Only 9 per cent of parents thought the diploma should be optional.