[guidoism]

I'm at 48 keys right now, but I would like to counter that it's not just key presses you should care about, but also movement of the hands. My setup definitely isn't perfect but your example is exactly the kind of key sequence I have optimized for. Having parenthesis and the various brackets on the home row or very close is super awesome for programming.

Honestly, you don't need to go down to so few keys, just program your keyboard to have one more layer that puts those special characters into a better place for you and I think you'll get 90% of the benefit of the OP's keyboard.

[ZeroGravitas]

What actually tipped me over to doing this 'layers' thing, was exactly these keys being in different places on different keyboards.

Having (){}[]-+ in the same place and easily touch-typable was much better than having them in different places depending on what I was typing on (dvorak already has < and >, ' and " period and comma in a sensible place).

[guidoism]

Exactly! I can hold the layer key and do the entire ()[] sequence for links in markdown in one go and every time I do that it makes me smile.