same here, I've had some custom axle jobs made before on Hadley hubs to fit various bonkers frame combos (think ellsworth with 20mm REAR bolt through steeped down to 14mm.. )
was probably someone who worked/knew a machine shop and decided to convert rather than buy a new hub.
I've been toying with the idea of similar on Pro2s recently, swapping for bigger internal diameter bearings, to enlarge the axle diameter and drill off-centre to try and make an eccentric SS axle similar to how the WI ENO hub works.
Matt