In viewtopic.php?f=59&t=63668 it is said that the term "this personality" always applies to the personality that the Soul Jar is attached to at the moment that one looks. In essence, this is saying that the ability on Soul Jar, which creates an ongoing effect, is in fact integral to the Soul Jar rather than to the performing personality.
It has long been my understanding that when one uses an ability on a spell or item, "this personality" refers to the performer. Thus, the spell Companion Spirit works. In the referenced ruling above, the following steps would occur:
Companion Spirit 1) Limited: If this Shugenja is Human, bow him 2) and destroy this card: 3) Create a Cavalry, Samurai, Spirit Personality whose base Force, Chi, Gold Cost, and Personal Honor are those of this Shugenja, waiving the Samurai's Gold Cost.
By my current understanding of how to read "this personality" (or "this shugenja" since Shugenja is the keyword that the spell looks for) there is no personality to draw stats from and all mentioned stats are set to zero.
Is this correct?