I added a little cornflour to the mix to see if it would soften the dough. An unnecessary addition so I discovered. If anything, it dried out the dough a little. (BTW, if you have littles have you ever made gloop? A bowl of cornflour and water mixed together constitutes a very good rainy day activity that feels a little like a scientific experiment).
A more worthy addition was a few drops of lavender essential oil, the scent of which is reactivated each time warm hands work the dough.