Speaking on that, I wanted to make sure I understood the change - it would have reduced the effectiveness of scattering shots which manage to hit another unit aside from the gun's main target as caused by focus fire being off on the gun, right?
no the damage aoe profile means at the ranges (near / med / far) it will do the base damage x that.
For example
lets say the profile is (1 near / 0.5 med / 0.25 far)
and the base damage is 100.
at near assuming it is a hit and scatter is not a factor you will do 100 / 50 / 25 damage at the ranges.
the changes to the HMG profile were to reduce the damage it did at ranges as it was looking like it was killing too many models thus compounding the "manpower bleed" of the USF. However like I said earlier with the buff to rifleman it did not seem necessary anymore.