Второй момент — спасибо. Уточню в переиздании, фраза потеряна переводчиком. Хотя если читать не буквоедски, то там вообще написано про все шаблоны, а взрыв гранаты — шаблон.
I don't know if the Russian version allows it for all Area Effect attacks or just doesn't specifically use the examples of grenades (or mention artillery) or perhaps has some other limiting description. Really though like movement, if both the players and the NPCs use the same rule, it's still likely balanced in the end.