It is good to look for “deeper explanations.” So, I am not trying to discourage such questions as the one from Jorg.
– But in some cases, there are no such explanations, like the one I mentioned above for 17 cittas in a citta vithi.
– Of course, I could be wrong in this particular case. If there is such an explanation, I would like to know too. If I come across one, I will post it.