I insisted until Per Alm gave me a statement of what happened at the symposium !!
At the Nordic Neuropsychology Conference a 3 hour symposium on stuttering was held. The speakers were Katrin Neumann, Gerald Maguire, Hans-Georg Bosshardt, and Per Alm. (Lutz Jäncke was unfortunately unable to attend.) A general conclusion may be that the understanding of stuttering in relation to the functions of the brain is developing relatively fast for the moment. However, it is also becoming increasingly clear that the issues indeed are very complex, and will require a broad range of research approaches for a long time. One aspect that may be mentioned is the progress in brain imaging, which seem to start to shed light on mechanisms for late recovery of stuttering (in teenagers and adults).
I agree with the complexity part. We have hit the complexity wall. Stuttering is a malfunctioning of a highly complex system of interacting modules. I fear a big obstable is that the majority of researchers are intellectually badly equipped to tackle these challenges: we need brains with multi-disciplinary expertise combined with extraordinary lucid conceptualisation ability, rigorous quantitative thinking and an understanding of the nature of complex systems.