Hi Azizi,
I promised not to say anything more about the squiggly-doodle--well, not specifically--so I'll just address your question.

Do you also think that exploring possibilities about old subjects is anathema, even when there is old and contemporary information that appears to suggest that the new way of thinking about something old might be valid, at least some of the time?

No, absolutely not.

You also asked:
[Gibb], I'm wondering what kind of evidence you would consider to be credible.

That which can be observed is evidence, including first-hand sightings and written/oral statements. However, one must treat statements critically, as you point out. Most importantly, evidence must be taken in context, and that might be what determines "credibility."

If Hugill didn't provide any documentation that the phrase "do do" or "doodle" was the same as or could be the same as the phrase "dou dou", and if no other White collector at that time noted that, are you saying that means that the phrase could not have meant the same thing as "dou dou"?

Quite simply, Hugill never says "do do." He says that his Bajan "friend," Harding, used both "do" and "doodle" indiscriminately. I know your question was originally addressed to Q, but my answer is that no, I'm not saying it could not have not meant "dou dou." I think it's very unlikely however, and I've already stated why.

Coming back to this,
Do you also think that exploring possibilities about old subjects is anathema, even when there is old and contemporary information that appears to suggest that the new way of thinking about something old might be valid, at least some of the time?

I think I'm pretty much in 100% agreement with your attitude. That should be clear from the fact that, as I said, I re-opened the thread to add a new possibility to the mix.

Like it or not, and you'll forgive me for saying this, but there is nothing "older" and "Whiter" (if we're labeling schools of thought ethnically) than the de-contextualized comparative etymology approach (hence my subtle jab at 19th century philology). It is a completely valid methodology (which I use often), but there is absolutely nothing new about it, even if its focus happens to be on non-White areas-- which in fact it very often was (being the method par excellence of Orientalists). That approach assumes that the utterance has a declarative "meaning," and that somehow its meaning can be separated from its context (i.e so as to be compared with other "units"). This "old White" methodology (which of course I mean totally ironically) works best to analyze other mainstream "old White" texts; sometimes it yields nothing when dealing with culturally different texts that make up say 50% of sea chanteys.   

The best method? A combination of all methods, no holds barred.