Well the simple answer is that was the shape and position of the FFs on this model.
But, I love 'em, I find the shape tres elegante and kind of why I chose this pattern to build. Now, I look at other basses and think gee, those are tiny FFs!!!!
There seems to be no reason why they cannot be so; a broad centre table maximises the connection to the upper and lower bouts, and the long ffs give lateral flexibility where it counts. The wood on the outside of the FFs does not seem to serve any acoustical - or even structural - purpose anyway, so a bit less won't hurt.
And ... big holes let big notes out
