Zero experience here but it sounds like discharge black, with the right pigment level would make a perfect halftone key color. I almost never use an opaque black for halftones, typically a very transparent black. A weak clear discharge base + just enough black pigment, over printed to a degree on the CMY and White might look amazing. I would imagine you would want to let the other four colors really spread out so the more transparent/weaker black is coming down over top and providing all those bonus shades. That's weird actually if you think about, you would encourage and allow gain on your colors to get more blending and then keep the black absolutely perfect to pull it all together. Huh. I'm just talking out my arse here.
I'm really looking forward to getting my dots to blend out completely with discharge and doing tons of overprinting. Though I never use true process to print anything, this stuff excites me.
Back to the less exciting task of lint control...