I think if someone referred to “the Travises shared given name” without adding the extra “es”, my brain would get stuck on that for a bit. I don’t know that that would be the case for most people or not. But if someone were talking to me about the name shared by multiple people named “Travis”, my brain would churn less, get " stuck" for a shorter time, and be less likely to have to catch back up to the conversation if the extra “es” was included.

Without the extra “es”, it feels like it could get a little “garden-path-y.” Like:

• “The Travis…”
• “The Travis” sounds like a pretty pretentious way to be referred to.
• "…es"
• Possessive. 'k. What does he have?
• "shared given name…"
• Oh, so “The Travis” was magnanimous enough to offer his name for consideration when it came time to decide the name of… maybe one of his relatives’ newborns…?

Right? Not to say I wouldn’t expect to catch on in a couple more words there. And also more realistically, my brain wouldn’t be stuck on this interpretation in the conversation, but more “suspending judgement” and holding both possibilities for interpretations in mind until something resolved the question. But speaking just for myself, I think my brain would have to go through all those machinations if the extra “es” wasn’t there. And that requires more wetware cycles than if the extra “es” wad there. If it was, it’d be unambiguous immediately after the second “es” that “Travis” was both plural and possessive.

(To be fair, after the second “es” another possibility would be that we were talking about multiple groups of people named “Travis”. Chapters of a club only open to people named “Travis” for instance. Kindof like the word “peoples” which is similarly “double-pluralized”. But it seems to me unlikely my brain would jump to that possibility the way it might jump to a possessive form of the title “The Travis.”)

Also, it’s very possible my brain works differently than most. I think I have a pretty “stilted” manner of speech. People occasionally poke gentle fun at me about it. (All in good fun, mind you.) And it’s possible my brain doesn’t process speech quite like most people’s do.