I posted similar comments over on Diercks' blog and Michelle posted a comment that helps illumine the situation.
So here is the clarifying material concerning W as a vowel from David Black and Michelle Mosher.
Dave Black directs us here.
And Michelle writes the following in the comments on Diercks' page:
so W and Y aren't really vowels, but they're not really consonants either. some linguists call them "semi-vowels" because of the way they're sort of in-between.
W is actually a lot like U (and Y is a lot like EE). So if you say "snow" with a "u" at the end instead of a "w" it'll still sound pretty similar. Try saying "snou" (with a normal "oh" sound and a normal "uu" sound.
It's easier to tell with a word like "water". Try replacing the w with u: u-ater. Now say it fast.
so yeah, W and y are kind of vowels, but not really.
So there you have two very knowledgable people helping us understand the notion that W can indeed serve as a vowel.
Maybe they have changed my opinion on the matter (yes I know this contradicts what I said in my earlier post) or maybe not. I guess I still need to think about this some more.
Hopefully some Lent thoughts will be posted soon.