Two questions on the same thing: Question A and Question B. Closing either as a duplicate of the either seems suboptimal for different reasons. Could a mod merge the two questions?

Now there's a hidden gem if ever I've seen one. What a fascinating analysis.

When a vav starts a word and has a dagesh inside, and is devoid of any other vowel, is it the vowel oo?

You see, I am not sure whether vav can be a vowel when it starts a word.

@ktm5124 Yes, the "oo" can begin a word - the only vowel sound in biblical Hebrew which does. "Vav with dagesh ... devoid of other vowel" is a vowel (called "shureq"), and that's not a "dagesh", it's a vowel sign. (There are various names for dot-in-letter when it's not doing the dagesh job.) See GKC para 26a, part 1 for the explanation.

@Dɑvïd My sincere thanks... I appreciate your clear explanation.