I think this is one of best exaple where optional rule can be aplied.
I thought this is the reason we have those not-rolled dialogue options. O_o
You know ...
[Druid], [Fighter], ... but also [Drow], [Baldurian], etc ...
I mean PC game is explicit environment after all ...
We are unable to get into any unimplemented dialogue situation ... and while possibilities can be (and sometimes are) oversighted ...
We get this unfailable options for our unfailable situations ...
So in your exaple Gale would (or should) have options:
[Wizard] Weave is just other word for Magic.
[Insert skill here] *try to explain it as thoroughly as possible ... yet easily so that kid understands*
The joke is that currently in the game we sometimes have it as:
[Arcane magic] Weave is just another word for Magic. - ROLL
[Wizard] [Arcane magic] *read the full lecture to the kid and tell him the full story about Mystra* - ROLL
