My attention was drawn to a somewhat sensationalised account in today's Daily Mail about scheming by a certain Kenneth de Courcey to enable the Duke of Windsor to return as Regent for the ailing King George VI. The article is interesting, if it is accurate - and it does contain errors: Queen Mary was not "German-born" unless Kensington Palace was in Germany in 1867 - in recording tensions in and around the Royal family in the later 1940s, and centred on the Mountbatten family.
Any possible discussions, as it recounts them, sound like late-night ruminations that were never going to be attempted - other than by someone like de Courcey who would seem to have been the type of social butterfly attracted by and to the erstwhile King Edward VIII. As it was whatever was discussed or thought about - and whether available or not to researchers today - does not seem to have been pursued by the Duke of Windsor himself when he might have. That suggests he realised that, when it came to the point, he had renounced his rights in 1936, and that was that. He, and his wife, might dally with ideas of some sort of return, but that it would not happen was pretty clear to all concerned.
The article, by Christopher Wilson, can be read here.