I've always been puzzled by that reference since each story had mostly different characters but oddly many of the same cast. Was there a deliberate reason why Ford used different names for the Duke's lead characters but kept the same character from Victor McLaglen and Ben Johnson in Rio Grande and Yellow Ribbon?
Both Grant Withers and George O'Brien were also in Fort Apache and Yellow Ribbon but played different characters in those films. So if you think about it, there are a ton of continuity problems when you see one actor playing the same character the same way but our lead star playing a character similarly but with a different name.
Now thematically they're all the same, but that's about where the comparisons end if we're wanting to link the stories as one continuous narrative. The funny part for me? Yellow Ribbon feels like the third film in the series because Duke's character is older and retiring. So it's kind of odd to see him under a different character name playing a younger version of what you would kind of perceive as Captain Brittles.
I know, I know... Your head hurts when you try to line up the logistics of it. I'm just surprised why Ford didn't just keep the same characters for all those actors who made encore performances since he was strolling through that same era.