Why don't you believe me?
Seriously, I'm a weasel.
"Play Note: LOS, while not a major problem in most of these battles, because of the flat terrain, is often a cause of “player tension”. We suggest that missile LOS rules be interpreted strictly, while LC LOS rules 4.25 be interpreted liberally. The former are trying to shoot at a target; the latter are simply trying to see if everyone is in place."
Can someone give me an example where, as a player, I am required to guess the intention of the rules?
I would guess it is referring to the case where LOS would be traced along a hexside of a hex with blocking terrain. In this case, LOS would be blocked for missile fire, but would be open for LC.
This example is given explicitly in some of the other GBoH rulebooks, so I assume it would be similar here.