I'm not sure if it even makes a difference, maybe it was just the way that, for example, C1 v7 showed the selected color area. (It would seem this way, since "Key exact color correction" shows the same behavior). The article does not mention it by selecting multiple points for a correction, and in any case, the tool works as in this example with only one point in C1 v11.
The "multiple choices" in the article refer to multiple corrections, because in C1, you can only change the tone by ± 30 ° – for example. to go from red to cyan, you need 6x + 30 ° layers for the same object and the same color.