OK, enough of this silliness.
I've gone up to Danshui several times since I last mentioned going there a few months ago. The trips haven't been dress rehearsals, more scoping out the coast for other location options. In the end, the best location is the first one I scoped, right at the mouth of the Danshui River.
From here on in, I think I'll start going to Danshui as often as possible as dress rehearsals. Preparing myself as if this might be the attempt.
One thing I found on my most recent trip was that the attempt will be conditioned on coastal conditions. The waves along Taiwan's coasts can be pretty rough, making my plan difficult. So a final 'go' will be determined by getting there and finding the sea is relatively calm.
I've been learning things each time I've gone up to Danshui about how I want things to be and things I want to take into consideration (such as what is not a legitimate consideration). So much does not matter anymore that most "considerations" I've had in the past are no longer valid.