I just did a thing.
I have a Dingwall Combustion that I love. I customized it a little while ago by putting in the Fret Nation 6-way switch that gave me the solo middle pickup. That was good, but then I heard the Dingwall Nashville Combustion "all pickup combinations" video and I wanted to try it out. So I figured out how to rewire my Combustion as a Nashville Combustion. I pulled out the 6-way switch, installed a blend, put in a push/pull volume pot for active/passive switching, and installed a DPDT on/on/on mini switch for the special sauce Nashville middle-pickup switching. A key difference that I picked up in the Dingwall Facebook group is that the middle pickup on a Nashville is wired in series with itself, where on a regular Combustion it's in parallel with itself. So I made sure to make that change.
I love the solo middle pickup in series, and I like the blend knob, but I wasn't super happy with the mix of middle pickup and blend, it just sort of seemed thin and not super differentiated.
So.
I had wired the blend and middle pickup on/on/on switch so those two outputs were in parallel. I thought, "what if I could wire those in series?" It took me forever to figure out how to wire up the DPDT on/on/on switch to make that happen, but I did. So now, the middle switch position has blend in series with the middle pickup.
Holy moly, it sounds AMAZING. When the blend is set to the bridge or neck position, it sounds terrific with the middle pickup. Ballsy, nasty, super powerful. But when the blend is in the middle, it is just a MASSIVE sound. Unbelievable. I love this thing. All I have to do is be careful I don't blow the windows out.