@LiamN I’ve heard the mars probe story. I’m more suspicious the z-error was Carbide motion bug, that toggling mm to inches in the interface somehow messes with the homing, but that’s speculation. It’s behaved reasonably well for me otherwise once I realized that the touch probe and alligator clip touching is what was causing the bit setter cycle to fail and now keep them purposely apart after use. The unusual plunge depth on an unpredictable basis appears to happen to others, too (Z-height issue with bitsetter - #11 by WillAdams), so I just kept my hand by the e-stop just in case after that.
Also, I second the idea that machining seems to be about measuring, workholding, and probing – that’s just not what you see in the advertising.