Jigsaw evidence

That is extremely strange.

The writer evidently meant to allude to a "jigsaw puzzle," the kind in which a picture is pasted to a board and the irregular pieces are cut apart with a jigsaw (a saw used to make fine irregular cuts).

So a better way to write the sentence might be, "Cost-benefit analysis could be a useful tool for examining the evidence and showing how it all fits together."

Frankly, Olga, I'm not surprised that you're confused. The sentence you quoted should win some kind of award for gibberish. It is so hopeless in so many ways. :)

thank u so much :)
u are absolutely right - this way the sentence makes sense

Yes, that's interesting - while evidence may come in pieces, I don't think it normally comes in the form of a large and dangerous piece of industrial machinery designed to cut curved shapes out of flat pieces of wood. But then, I am not an evidence expert, so I could be wrong.

In the UK, most references to "jigsaw" imply the puzzle game, rather than the tool from which it is formed. "Puzzle" tends to be disregarded in conversation, more often than not.

Any metaphorical usages of "jigsaw" thus make sense when this mental image is conjoured.

I guess it's a British thing.

Which doesn't at all change the fact that Olga's quoted sentence is as stupid and mechanical as a bag of loose car parts.

Thanks to all once again
It's really a British thing - got to translate lots of presentations each sentence of which looks no better than this one :(

'Final piece of the puzzle' would have been a better way of putting it.