does Lightroom 6 include the HSL panel? why don't I have it?
In Develop press Ctrl+3 (Cmd+3 on Mac)
It does. You've probably hidden it inadvertently, so right click a panel header (like Basic or Tune Curve) and you should be able to make HSL/B&W available again.
LR6 and earlier versions definitely include the HSL panel. If you don't see it, right click on any other panel header, and select the item labeled "Adjustments."
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