Danpri,
The USSF Advice to the Referees quoted above is the position paper you seek. THe Advice is the "fleshing out" of the rules with practical applications that is the official word on interpretations in the US.
Also Jim Allen (National Instructor and Assessor) from the USSF has a web site that gives opinions on issues posted. These are also considered official interpretations from the USSF.
The link for his site is:
http://www.drix.net/jim
you can look at the archives of previous questions as I am sure Mr. Allen has touched this topic.