Walkin Ins. Who Knew?

http://www.greatdreams.com/walkhow.htm

I have been reading about soul transference.  Quite interesting.  An excerpt:

HOW THE WALK-IN EXPERIENCE WORKS

When the individuated, embodied part of Spirit, the Soul, has completed what it set out to accomplish in a lifetime, it has three basic options: take on a new life goal (Reincarnation-in-Same-Body), die, or walk out. If the Soul chooses to walk out, an agreement is made with another Soul to walk-in and continue the embodiment. This is not possession. It is not a requirement that a person be a walk-in to ascend. It is simply an individual agreement and another way of entering onto the planet.

More:
 
There are many reasons for a Soul to walk-in but the main one is that it is usually quicker to integrate a new Soul into a new body than it is to grow a body from scratch.

And this one:

Usually, there is a "try-on" period of a few days or weeks or months when the new soul tries on the body before the actual transfer. The personality may or may not be aware as it often occurs while sleeping, meditating or channeling.

And:

The one thing that walk-ins have found necessary is to be very gentle with their physical bodies. The body is not a vehicle but a co-creative partner in our life experiences. It takes time for the physical body to work through feelings of dying, rejection, abandonment and grief. But when the body consciousness understands that the walk-in Soul consciously chose this body, loves this body, and is willing to work as a partner with this body, then miracles can happen.

Wow.  I wonder how Greer has coached Evie in this?  Will this happen before I meet Seola?  Do I have to be there for it to happen?  And who decides the right moment?  I will have to do more reading.