To further muddy the water. With other test data I find that the result with the above code is not quite as desired, as I initially expected (thus the plea for help). While it returns a legal result, its far from optimum. For instance:

 
&pseudoKnotPairs(qw/0 100 1 99 10 88 11 99/);
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Will remove the first 3 pairs. All that would be necessary is to remove one of 10/88 or 11/99 and all three remain pairs would pass the mystical "nested" test.