There is a difference between "How sure are you that if we looked at the coin now, it is heads?" and "How sure are you that if we looked at the coin only once, at the end of the experiment, it is heads?"
In the first variant, the thirder position is unambiguously true.
I the second variant, I suspect that you really need more precision in the words to answer it. I think a halfer interpretation of this question is at least plausible under some definitions of "how sure"
Unless "how sure" refers explicitly to well specified bet, many attempts to define it will end up being circular.
If I am very sure of something, I would be surprised to see the opposite. I don't need a bet to determine whether I'm surprised or not.
The most recent post in December's Stupid Questions article is from the 11th.
I suppose as the article's been pushed further down the list of new articles, it's had less exposure, so here's another one for the rest of December.
Plus I have a few questions, so I'll get it kicked off.
It was said in the last one, and it's good advice, I think:
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.