Word difference between BMM and TW that led to a friendly disagreement because I didn't have the BMM on hand.
BMM
6th printing, pg 43: Hull Integrity and Breaches:
"Whenever an underwater location takes damage (such as the legs of a ’Mech standing in Depth 1 water), its controller rolls 2D6...."
TW
10th printing,
pg 121: DAMAGE: Underwater Units:
"Whenever an underwater unit takes a hit that inflicts damage, the controlling player rolls 2D6..."
pg. 56: Underwater (Non-Naval Units):
"To be considered underwater, a unit must be completely submerged. It cannot be in Depth 0 water; ’Mechs must be in at least Depth 2 water, or at least Depth 1 if prone.
Friend's reading of TW was both strict and earnest — a 'mech standing in depth 1 is not an "underwater unit" and so does not take breach checks for leg hits. They rationalized it as due to (hand wave) 'difference in pressures' between a unit fully enclosed in water vs. one poking out.
