[quote=@Mammalia]
<Snipped quote by Dynamics>

But what if, for example, your strongest move is not something they are vulnerable to? What if you have other moves that they may in fact be more vulnerable to? For example, you could hit Ruby with your strongest force possible, but you would fail. However, you may hit her with something she is not invulnerable to, but you cannot do as powerfully, but she may still be taken down.

<Snipped quote by Galaxy Raider>

*continues to watch, ready to help if it is needed*
[/quote]

Then it makes no difference that she knows the strongest move. Furthermore, I did say that you should know what your opponent could evade, which includes ineffectiveness.