I am quoting Peter here. I agree completely. There are so many ways to do this exercise, and many different things come up. Peter, doing it with other people is an excellent practice. Did you do it with people who were present, or with people you remembered?
The question about how the object (now subject) knows can drive you crazy, because if you knew, then you would be the one knowing. The object has to know in its own way. There is also a subtle distinction here, being 1) letting the object be the knower, and 2) taking on the identity of being the one who is known. I could imagine this second possibility as when you allow a friend to know you, and open yourself to being known.
I will write a separate post about how I have been exploring this exercise, which this time, as always, is different from every other time.
Jack