Hi Dryden, I think that a more accurate hint might have been, "Silent letters, pseudo-silent letters, letters the setter believes to be silent but are not, letters that may be silent due to mispronunciation."
I'm not talking about regional accents, simply about what letters are intended to be pronounced. When making an assessment of this puzzle it might be all too easy to allow latitude to the setter on grounds of regional pronunciation. Except that the puzzle features in a national newspaper.
A possible saving grace is that (it seems) everyone was able to complete the puzzle without needing to indulge the setter's whimsical letter choices, and found an easier route via google. Though if it is the only route to solving the puzzle, then the google route attracts criticism of a different kind. But without such a short cut being in place, I don't think this puzzle would have been fit for publication.