I know people cop out of this question and pretend like "No", because it's easier to mentally digest. The correct answer however is Yes, under the reservation that sometimes the correct answer implies an expansion of the domain. Which, of course, is mandatory not optional.

It occured to me that this model fits perfectly into modal logics, but these also use doxastic elements (i.e. the notion of belief and whatnot), simply because some questions, such as the one posed above, might not be answerable in practice. This wouldn't make the model any "more or less valid", but it would make some of its assumptions more precise I suppose.