Claim 10.11 implies, for example, that the
reversal defined by the gray edge (10,11) is a safe proper
reversal for the permutation of figure 10.10 (a),
since it corresponds to the node with maximum unoriented degree
in the happy clique
.
On the other hand, the
reversal defined by (2,3) creates a new unoriented component,
as it yields the permutation shown in figure 10.11.