I just asked a fellow who I see on a regular basis about this, in
person, "When you use the word \"doubt,\" do you mean the same thing as
\"question?\"" He unhesitatingly responded, "Yes." He began to add
detail, but his wife interjected about "grammar" and so I didn't catch
it. Then he suggested that his experience with North Americans was that
some words and grammar were different than the British influence that he
believed was responsible for his intended meanings and usage.
Interesting... Though off-topic, of course.
Seeing as how we've just seen "doubt" used again, I'll share that:
I had another, lengthier conversation with another couple I see on a
regular basis (and who happen to know the first couple that I
doubted^H^H^H^H^H^H^Hquestioned) and they suggested that they understood
the subject of a "doubt" to be two-valued versus the subject of a
"question" being many-valued. This wasn't the same exchange as the
first fellow I asked, since he seemed pretty sure that using the terms
interchangeably was all right.
The example one of them gave was, "I have a doubt that you gave me
enough cash money." They also suggested that they (the two of them) use
the word to mean something like "disbelief," and "do not agree."
They also suggested that from time to time, when they lack the
vocabulary (she wasn't lacking "vocabulary") to express something in
English, they'll substitute a similar word, even though they can tell
that it doesn't belong. I'm quite certain I'd do precisely the same
thing; association.
So as far as "surveying" goes, I have asked two couples (who know each
other) and have gotten two different answers.
I wonder if a "bedrock doubt" is about something "fundamental" or
"foundational" or the "basis" of something... For whatever it's worth,
Google translates "I have got two bedrock doubts" into some text which
translates back as "I have found the suspect."