So? If you bother to read what I said ...
Yes, I bothered.
... which was, and I will rephrase it so that it is clear, that if the search fails to find anything and it is deemed useless to continue ...
Here I read a sentence in the passive voice.
The person or persons doing the "deeming" are not identified.
It is not a precise sentence, and so it is susceptible to various interpretations.
Of course, it is a tautology that if TIGHAR "deems" (judges) that it has exhausted both the search space and methods of searching, it would be "useless to continue."
I presumed that you were not speaking tautologically.
... then any further searching would be a waste of time and resources which I would think is quite irrefutably obvious and because of that I doubt that TIGHAR would disagree.
Here is the person who seems to be doing the deeming: "any further searching would be a waste of time and resources, which
I would think is quite irrefutably obvious."
So it is not TIGHAR coming to that conclusion in your hypothetical situation; it is yourself ("
I would think ... quite irrefutably obvious"). You can't be imagining that TIGHAR has made the decision, because you are indicating that TIGHAR
ought to see reality the same way you see reality. You announce that what is obvious
to you (a subjective judgment) should be "irrefutably obvious" to TIGHAR.
I don't know whether anything "irrefutably obvious" will come out of this year's expedition. I'm keeping an open mind. I do believe it will be interesting to see what the deep water search will find out about the area around Niku.
... remember that the objective is finding Earhart's Electra not proving that it landed on Nikumaroro, if somehow the first has segued into the second then I suggest that TIGHAR has a problem.
It's too early to tell whether that transition has taken place.
If TIGHAR decides that it has explored all explorable areas by all financially possible means, it does not follow that its only choice is to expend time and money on another hypothesis. TIGHAR's purpose is not to find Amelia's Electra; its purpose is "historic aircraft recovery." There are lots of other historic aircraft to pursue. TIGHAR's
opinion (judgment) could well be that the Niku hypothesis is true, but not provable. The failure to find evidence does not prove the Niku hypothesis false; it may only prove that all evidence has disappeared from TIGHAR's view. You may be familiar with the saying of Carl Sagan that "absence of evidence does not mean evidence of absence." Even if we imagine that all of TIGHAR's searches fail to find "irrefutably obvious" evidence that the Niku hypothesis is true, it does not follow that the failure of the search proves the Niku hypothesis false.
There are two and only two possibilities about the Niku hypothesis: it is true or false. There are two and only two possibilities about evidence of where NR16020 came down: it exists or it does not exist at the present time.

You seem to be reducing the logical possibilities to the top line: search Niku or search elsewhere. But TIGHAR has the option of giving up on Niku without having to make a commitment to search elsewhere.
Asking questions Martin is not opposition it is simply asking questions - rather like Freud's cigar which is apocryphal anyway.
I didn't see any questions in your post. And yes, I did read it. Every part of it was in declarative sentences, some more revealing than others.
Now I'll bet you take each word in that reply and offer every possible alternative interpretation of what it could really mean but what it means is what I said. Sometimes a cigar is a cigar however apocryphal.
Yes, I offer alternative interpretations of what you wrote because what you wrote was ambiguous, at best. And yes, I offer alternative interpretations of what is and is not "irrefutably obvious" because I do not share your philosophical standards for deciding what is "irrefutably obvious."
I'm pretty sure that this is what you were trying to say:
If the next trip finds conclusive evidence, which it now must, that Earhart and Noonan met their deaths on the island then good. If it doesn't then I would say that it is time to consider other options. As for my preferences as to their fate - I admit I have no idea, if I did and had the proof we wouldn't be having this discussion. But questioning evidence claims is what people like myself do, that isn't negativity it is simply working through the data. Oh and it isn't Mr McKay it is actually Dr McKay but you can call me Malcolm.
So, Malcolm, I disagree with your personal
opinion that "the next trip" must find "conclusive evidence."
I disagree that if the next trip does not find "conclusive evidence" that the only alternative is to investigate elsewhere.
These two propositions are not logically or existentially the same:
"TIGHAR has not yet found conclusive evidence that the Niku hypothesis is true."
"TIGHAR's failure to find conclusive evidence for the Niku hypothesis proves conclusively that the Niku hypothesis is false."
I'm very encouraged by the fact that you don't mind people challenging your evidence claims.