I played a game yesterday and it often seemed better for vehicles to charge infantry using their impact ability with automatic hits rather than firing their weapons. It seemed a little odd I wondered what the rationale was behind it. What does the phrase "clear path to reach it", it being the target unit, mean in the melee rules? Does a vehicle need to have line of sight to the target before charging? Does the charge have to be in a straight line, eg, can the charging vehicle swerve around terrain to hit the target unit if it has the movement to do so?
I can't speak to rationale, but clear path to target means just that. You must move around terrain and other units to get to your target. You do not need line of sight, just enough movement to reach your target.