Från Intro...
Concentrate on what the rules do allow; not on what they don’t specifically prohibit. For example, if a rule states that a MMC can perform a particular action, then only that unit type can perform it—don’t think that several SMC can do it simply because the rules don’t list that type as being unable to do it. Play by what the rules specifically allow or disallow, not by what they don’t specifically prohibit. For example, rule C13.8 prohibits bazooka fire at a target two or more levels higher in an adjacent hex. The rules say nothing about firing a bazooka at a lower elevation target or at a target two or more levels higher in a non-adjacent hex; therefore such fire is allowed.