My attempts to do this have been interrupted several times this morning.
Rehearsing the day’s events in total doesn’t work for me, or seem necessary. For example, later today I’m going to go for a long walk on my own. Beyond resolving to go on the walk and deciding on the route, rehearsal in advance seems pointless. It seems more useful to rehearse the events which I anticipate may be challenging, such as the meeting I might go to this evening.
The quote from MA: Seems to me to set a high bar — training yourself to only think thoughts that we would not mind other people knowing. But, the impossibility of the task does not mean the attempt is not worthwhile.
On the other hand, how healthy is it to suppress our darkest thoughts and desires? If we suppress them, they remain unexamined, and they may surface in another form. The result could be passive-aggressive behaviour, or worse.
But, maybe suppression is not what MA means. If I, e.g., envy what other people have, then mindfulness will alert me to that envy, and I will then seek to replace my envious thought with generous ones.