Spear infantry in 2 ranks have a +2 vs mounted, +/1 vs any and ...+1 vs infantry if in one rank unless they are ME
To be able to move a file to create a new fighting file it must not be engaged
Now what about a second rank of hoplites , SP , that faces "common" infantry . Is the second rand engaged as it gives the +1 ves "others" or is it considered not engaged as it is not needed as per + 1 vs infantry if in one rank unless they are ME
Any rank that is contributing to the melee by either contributing to a claim or cancelling a claim is engaged. So against melee experts, 2 ranks are engaged. Against other foot, 1 rank would be engaged.
Thank you