Ian's knot saved me some time in the past decade or so.
Is there a knot with two settings for tying and releasing? Releasing it to a point that allows taking off the shoe and pulling somewhere else to fix it firmly again?
It must be adjustable because laces get longer over time.
I love that BBC radio (today: BBC audio) series. It started before the inflation of 'alternative facts' and it is worth (and very funny and entertaining) to follow, how this show developed in the past 19 years.