I got this question from Quinn, who is in the Pluto in the Houses Facebook group. It is a wild group, fun and free. I will tell you my experience with these two placements. First of all they are very, very different, as in the case of a beetle being different from a dog. The Unaspected planet is a feral child:free to roam and learn about who he is with no parental guidance. He can become great because he has none of the usual restrictions. He can find his own way and become a superstar. For example, the Unaspected Sun can be a superstar in whatever field he enters. He may be a movie star or a star professor. He does have to unearth his Unaspected Planet through diligence and determination, though.
The Singleton seems to be more of a hardship. The person feels he must PROVE himself in the arena of the Singleton planet. For example, if it is one earth planet( a Singleton is one of anything–one earth planet, one fire planet, one square, one opposition etc), the person may feel the need to prove he is “earth like” i.e is practical, grounded and has common sense. If it is one fire planet, the person may feel the need to prove he is “fire like” i.e confident, vibrant and full of adventure.
I have used the case of the elements above. Now, I will talk about the Singleton with respect to the planets. If one has a Mars Singleton, one may feel one has to prove he is a go-getter. If one has a Venus Singleton, one may feel he has to prove he is loving. If one has a Moon Singleton, one may feel he has to prove he is emotional. If it is Uranus, the native may feel he has to prove he is a unique person, different from the crowd.Hence, we put this altogether and have a picture of the Singleton. I hope this is clear.
The Unaspected planet should have a clear explanation, I hope.