Hi Diogenes,I have my Neptune (10 deg) in the 9th house as part of a stellium with Mars (18 deg) near my mc (21 deg) and sun (5 deg). I was able to see people and their motives and how they really were, much easier--especially at work as well as people from my childhood and siblings. The good news is that it has stayed with me.
Neptune rules my 2nd house, Mars my 3rd house and the sun is the ruler of my intercepted sign in my 7th. I had a lot of disappointments with these same people--they were not who I had come to think they were--not my friends. The ruler of my 9th is in my 8th.
A good example of Saturn's final transit to my Mars and the ninth's house connection to my eighth was a girl from high school. We had reconnected at the last high school reunion (I needed to listen to my intuition). She would try to fleece me when the combined bill (8th house) for the food and one time drinks came. I also (out of the corner of my eye) saw her look into my wallet as I paid for my meal at a fast food place once. I finally got rid of her last year. She worked as a nurse and made good money and her birth day is the same year as mine and is only 16 days before, so we had a lot of 7th, 8th and 9th house contacts between us. I now also look at many of the others from high school differently as well. Many of their natal Neptunes would be near my stellium in 9th.
The first time transiting Saturn conjuncted my Neptune it took the illusion I had for accomplished people or business people in general away. I saw the ugly side of business and the glamour was gone.
Hope this adds some insight to your project.
Best wishes,
Spring