Conforming implementations of tools that build fully-merged topic map graphs are free to construct fully merged topic map graphs from well-formed topic map graphs in any way that, in any instance, results in a graph that is indistinguishable from the graph that would theoretically result by applying the process described in the following subclauses. The subclauses (and the paragraphs within them) appear in the order in which the steps must be performed (at least theoretically, for purposes of this RM4TM's definition of the merging process in terms of its required results).

If this is illustration and not required, then shouldn't this be a
non-normative appendix? The requirements of mapping to topic map graph
is normative, this particular illustration appears to not be normative
by the terms of this section. Merging is normative but that should be
treated separately as noted above.