Maybe markup messed up in your comment?

The real tests look like this:

      doc1 = "More (XXXXX) to muck up reg.*{99} [solutions]+";
      doc2 = "More (stuff) to muck up reg.*{99} [solutions]+";
      assertTrue(test(doc1,doc2));
      
      doc1 = "More (XXXXX) to muck up reg.*{99} [solutions]+";
      doc2 = "More (stuff) to muck up regZ*{99} [solutions]+";
      assertFalse(test(doc1,doc2));

      doc1 = "More ^XXXXX) to muck up reg.*{99} [solutions]+";
      doc2 = "More ^stuff) to muck up reg.*{99} [solutions]+";
      assertTrue(test(doc1,doc2));

How can this can be SAME (TRUE). doc2 has regZ* ???

doc1: More (XXXXX) to muck up reg.{99} [solutions]+
doc2: More (stuff) to muck up regZ{99} [solutions]+

spoiler flag... ;p

no, not efficient enough: you need a solution with O(1) time complexity (meaning: no loop at all).

I guess you try to build all the points? You need somethign more efficient, so another algo.