When we talk about how or why something evolved, it is common that some sort of scenario will come up. A scientist will say, well, this could have happened, and then that.
If one of these stories is offered you as evidence that things happened that way, you should complain.
However, such stories are very important to the process of science. A good hypothesis is useful. It suggests new topics to be researched. It suggests what to keep an eye out for.
(For example, the story might say things about a transitional fossil which has not yet been found. Or, the story might say where in the human genome to look for a certain gene.)
But these stories also have a second function. They are evidence that a scenario exists. Suppose I claimed that all of the ways to get from A to Z were "highly improbable". You could produce a scenario. If it isn't a "highly improbable" scenario, then you have disproved my claim.
(For example, I could claim that a feather is of no use unless it is as complicated as modern bird feathers. You could rebut this by showing that a feather doesn't need barbules and hooklets to be useful. And in fact a fossil feather has been found preserved in amber, and it didn't have barbules or hooklets.)