I was surprised to read the answers to a recent question on thickening - two of the three, including the accepted answer, suggested using cornstarch instead of flour to save calories.
I have always assumed that flour and starch are so close in binding power per weight that there is no reason to change any proportions when substituting, and also that the starch source doesn't matter. OK, I know about amylose and amylopectin being present in different amounts in different plants, but my impression is that the same amount of both gives a different thickened texture, not different thickness.
Now the answers and comments there contradict my impression. So, I would like to know: how much is the difference in thickness? If we take some reference, for example
5 g of cornstarch per 100 g water, mixed and then cooked until thickened
how much of some other starch (potato, arrowroot, whatever) and how much wheat flour (AP or 550) is needed to achieve the same thickness as the reference?