When I select to place a project, such as economy stimulus or research project, in the manufacturing queue, if I spend any points in manufacturing at all, I get a flat bonus such as +10%. This bonus applies if I allocate 1 manufacturing point or I allocate 100 points of manufacturing to the project.
This means that whenever I select a project, I have to change the economy wheel setting on the planet to have 1 point in manufacturing and the rest somewhere else such as either research or wealth generation. Otherwise I am wasting huge amounts of manufacturing points for no benefit.
It would cut down on a lot of micromanaging if projects would give a flat bonus even if no points were spent in manufacturing. This would allow me to just set my research planet to 100% research and not have to adjust the economy wheel to ensure no manufacturing points are being wasted on the project.
Alternatively, the benefits of any project could be proportionate to the manufacturing points being spent on that project.