Seems you have in the past "the position" of the click on the edge
Why not use a similar system? Just one click needing ;)
In any case if it's wrong choice, make undo and click the other side :)

Hi Pilou, I don't know.... it can get kind of hard to control things by a clicked on point when there are many pieces.

Also many people don't think about that - remember that is why I switched the blend to not work like that since it was a question that came up fairly often.

- Michael