I think one should be able, especially when trying to become a citizen of a particular nation, to speak and use the common language of that nation to a functional level within a certain amount of time. Icedog, it is apparent to me that your grandfather to his credit did this. Perhaps he did not speak any at home, and maybe he only knew enough to perform his job, but he was at least functional enough to work for GE. Right? Fluency may or may not come later, but there is no excuse for not putting the effort to become functional in the language. Otherwise where is the evidence one really WANTS to become a citizen, rather than just reap whatever benefits/escape some other nation he or she feels is worse....? Citizenship should be granted only to those who truly desire it, and not those who merely find it convenient or perhaps profitable. Honestly, I believe there are even naturally born citizens who based on their loyalties, should not be-but that is not the law.
Anyone attempting to be naturalized needs to convince the new country of his or her loyalty to, ability to function within, and allegiance to the new country, as it is not always a common thing to give up one's birth nation. It isn't a decision that should be taken lightly, IMHO.

John P.