In topic I have already asked) what's the difference and what to use? for ex I painted on alpha and painting will be like some dirty on surface...
I'm not sure I fully understand the question so correct me if I'm missing the point, but I use a brush texture while painting if I want the texture to influence the color of my stroke and I use a texture mask if I want to use my own color from the color picker but have the texture only define the shape of the brush and where the paint is placed.