When a parent checkbox gets checked off, all its children will receive a greying out effect, like shown in the screenshot below. Task 2 and 3 themselves are not checked off, whereas Task 1 is.
The strikethrough effect is currently the only difference between these two cases. The checkbox is checked for Task 2 and 3 as well, making them inconvenient to check off again. It might also give the wrong impression that they are themselves checked off. @Stephen_Dewitt requested to have the checkbox not checked when only the parent is checked.
In other words (pictures), after this gets implemented, the above scenario will look like this: