I don't know if I'll ascribe it to The Dean Scream because that happened after he already lost, as you note, and had self-kneecapped himself in going after Dick Gephardt endlessly until all of Iowa was offended at them both. (Bringing us the rise of his lord and savior, John Edwards.
)
The problem I thought tactically with the Swift Boats was probably that they ever did acknowledge it and try to counter it, even if using proxies, officially above board and on the record. Pulling the whole "it's offensive you even ask that, and anyway here are all my personal records and my best friends telling you otherwise, please read in detail, also please read my official campaign biography by your fellow reporter in detail" move always gives the media more smoke to chase after.
The fact that Warren decided she had to deal with this, of all things, before launching her campaign and being first out of the gate, probably indicates they had some serious polling feedback on it that seemed negative. Which probably is all you need to know about everything.
