From what I see the 0.79 scanlines are already hybrid, and the “scaline str. %” parameter controls from what IRE the scanlines will start to blend gradually.
ie. A setting of 25% will have not effect on IRE 25 and below so they will have 100% scalines, but will gradually brighten the black lines from 25 to 100 IRE.
Kind of looks like a simple linear equation where the slope is movable horizontally, as such:
The missing parameter is how quickly (slope) the filling of black lines occurs from the selected strength % parameter.
In that sense borti4938’s and paulb_nl’s final result is quite similar but differ at what point and how quickly the blending occurs.