The WhoAmI record can actually be created with LoginNotification.
For example, I added this rule to "When Login Notification is Received":
CREATE LoginLog WITH LoginLog.IsGuest=LoginNotification.IsGuest,LoginLog.LoginNameCopy=LoginNotification.LoginName,LoginLog.SessionId=LoginNotification.SessionId
Then I was able to display the current session's LoginLog record with this process:
FIND LoginLog WHERE LoginLog.SessionId=SESSION_ID()
DISPLAY MESSAGE LoginLog.SessionId
Lastly, I was able to create a query to show only the current session's LoginLog entry using this WHERE:
FIND LoginLog WHERE LoginLog.SessionId=Session_ID()
So, I can easily stamp any BO instance I create with the current session # of the guest (yes, guest users ARE processed through the LoginNotification mechanism) & easily retrieve current session instances of any BO.