Not relevant in 'my' version of the endgame which, from past experience, isn't as neat as Ifor usually manages (so I'm not discounting something else altogether... but if that turns out to be the case then 'mine' has to be a deliberate set-up - it's too pat to be otherwise).
Yes, that was a novel idea but it took a lot of explanation, and there was a lot going on in this one as it was. There were a few double obscurities in the clues (my pet hate).