It's quite remarkable when you think about it how fate can be both cruel and kind that even though things worked out well in terms of the history of the third tall man in LOTSW, it could have been so different.
Brian Wilde as Foggy probably wouldn't have happened had it not been for the unfortunate early death of Michael Bates. Brian Wilde was an excellent fit and as Foggy went on to become arguably the one that everyone remembers as the tall one in the LOTSW trio alongside Compo and Clegg. Wilde then left the series because he wanted to try pastures new and up stepped Michael Aldridge who was excellent as Seymour. Wilde then got a second chance after realising that the grass isn't always greener elsewhere, when Aldridge decided to retire to look after his ill wife. Again, had Aldridge wanted to continue there was probably no reason to bring Foggy back. In a sense we only have Foggy because of what happened to the others. However, I've also read that it was Wilde who suggested Frank Thornton as his replacement when he was ill. Wilde was never to return and Truly continued the tradition of the excellent, authoritarian, tall man. For me it ended there, as I don't think Hobbo as the final tall man was up to what had gone before. There again, he never had a Compo to deal with.