2.1.233 Part 1 Section 18.104.22.168, link (Linked Style Reference)
For additional notes that apply to this portion of the standard, please see the notes for numStyleLink, §17.9.22(a) .
a. The standard does not specify behavior when more than one style specifies the same styleId for a link.
Word ignores all but the last link to a given style.
b. The standard does not specify behavior for a singly linked style pairing.
If Word reads a singly-linked style pairing, it makes the linking bi-directional.
c. The standard does not limit the length of the value of the val attribute.
Word restricts the value of this attribute to be at most 253 characters.