Hi Geoff - preparing in word is always good practice. Even I as administrator get 'timed out' and lose stuff!
As to what gauzes do in a Jetex motor, Alec Hutchison maintained they had no catalytic effect, but Dr Ed has done experiments to show they do increase gas production. I will post more later when we can tease out the ICI pellet /WM gauze, ICI pellet/Sebel gauze, Sebel pellet/WM gauze and Sebel pellet/Sebel gauze effects.
Edward maintains, and I believe him, that gauzes do have an effect and increase thrust - which is what the flyers back in the 1950's felt to be the case.
Thanks Roger: "that gauzes do have an effect and increase thrust." Now that is interesting. I may have an explanation: You know how a flame front won't pass through a metal gauze? - hence the "Davy Lamp" used in mines. Could it be that the burning of the pellet is confined to a smaller volume by the gauze disc, thus increasing the burning rate, hence temperature and pressure - and therefore more thrust?