If you have situation

ZZZ
ZZZ


AAA
AAABBB
      BBB

This seemed to come up as part of another debate.  To avoid confusion I have removed it to here.

Each UG is 3 bases wide.  A is exactly lined up with Z. B is missile armed and within range of enemy Z.  BBB cannot shoot at ZZZ as although the left-hand base of B is within arc, it cannot meet the requirement for drawing lines without passing through friends.  B has to be in line with or in front of A to enable it to shoot.

Richard