This paper is presenting the results of the interviews of PE teachers and principals involved in an experiment consisting in doubling the number of weekly PE lessons in 10 Wallonian primary schools. Authors used an original approach to “reconstruct” an imaginary interview combining the answers of all subjects. The paper emphasized that practitioners’ views should be heeded when implementing a new programme. The practitioners pointed out that they need mainly to be encouraged when they have good ideas. If specific human resources and facilities’ availability were identified as determining factors, it seems that the main condition of success lies on the real wish of a teaching staff to put the physical activity in the centre of the educational mission of its school. It implies the leadership of the principal, the involvement of the PE teachers and the collaboration of each classroom teacher. A national programme imposed will not have a greater effectiveness than shared positive experiences intelligently highlighted by a marketing action if results of action research would bring objective support helping to convince those who prefer the security of the tradition to any calling into question and additional work.