The part she has a problem with is the section that says:
If you have an Element and use an attack of the Element that defeats your Element (e.g. you are Fire Element and use Deluge), your damage is cut by 25% of the base damage (rounded up).
If you have an Element and use an attack of the Element that is beaten by your Element (e.g. you are Fire Element and use Frost), your damage is cut by 25% of the base damage (rounded up).
In other words, this section means that if you're of a certain Element and use an attack of an Element that's either weak to or strong against your Element, you do less damage.
Our opinions stem from how we believe Elements work. Shrewdie thinks that Elements are like wizards using magic – they can learn whatever spells they like, and are able to learn and use certain spells more easily than others. My thought is that, when you say a pet has an Element, you mean that the pet only really has power over that particular Element. It can learn other Elemental attacks, but the ones related to its true Element are strongest, and because of its strong connection to this Element, it is weakened when using an attack of an Element that defeats its own (or is beaten by its own, because its Element crushes the power of the attack's Element).
Shrewdie would like to get rid of the above-mentioned section of the rules. I'd like to know what you guys think about the whole thing. o ^o
EDIT: The rule has been removed now. Thank you for your input~