I just noticed something odd.
I re-set my xyz esteps with M92 to the value i had used successfully to print an xyz cube last week.
I looked at my M420 V values and they were in the ~6.03 mm to ~7.58 mm as usual.
I then did a calibration of the bed from the touchscreen.
I then looked at the M420 V values and they were in the ~0.48 mm to ~2.06 mm range
I started a print and i noted the nozzle was lowered below the build plate by about maybe 1mm (i hit the power button pretty darn fast before the nozzle got to start temp!)
I think i may have found the methodology that cause head crash last week or so - be careful folks.
This seems to be only an issue if one does calibration AFTER setting xyz esteps.
–update–
Given this is a machine damaging issue i filed a github issue