Personally, I never liked the fuego box method unless I wanted to find out how low of an angle I can get on the board without booting out.
For me (mondo 26), boot center mark has been very important for both UPZ AND MS.951 to center the boots on the bindings (boot center mark directly on the center of the binding disk) THEN set up the appropriate binding angle. Mine is not at as far of edge as possible for the front at 60/57.5 for 20cm waist. I am always afraid to loose an edge Bc of overhang (50% of the time I don’t have that much angulation but I do other 50%). Nothing worse than loosing an edge at full speed Bc of overhang at Superbee chair at Copper. But then I loose an edge due to my technique sometimes anyways (gotta minimize an error )
If I didn’t center the boots to bindings, I felt the board tends to go in the direction which I am more leaned towards on the flats (awkward feeling). That is why I am surprised to hear people don’t center boots to the bindings. But there is no right or wrong in this sports! IT IS HOW YOU LIKE IT!!! I know I got weird set ups i probably got weird leg shape.
my 2 cents