That's great. What's also amusing is how you felt it necessary to provide the diacritical pronunciation guide for "Vaughan"... because I think to most native English speakers we can't imagine any other pronunciation!

I think native English speaker who had never heard of Vaughan (sure we can find some of those) would likely to pronounce it like "Vog-un" - /ˈvɒɡən/ or "Vog-han" - /ˈvɑːɡən/

This sent me down a mental rabbit hole, I think it's one of those interesting nuances that are rules that native speakers follow without being able to name it, or know it. I'm a native speaker, and also thought `vawn` was the most obvious pronounciation. I'm guessing it's because `augh` is perceived as a recognizable vowel cluster where `gh` tends to be silent (daughter, caught, naught, taught). The interesting twist for me is that `laugh` is in obvious counter example, until I realized that gh in final position (laugh, rough, enough) is almost always \f\. And further, in words like laughter, roughness, we immediately distinguish a modified root word from the lexical position.

Maybe there's also an interesting thread to pull on in that the pattern may be more pronounced for names (e.g. Hughes). Just ruminating here though, I don't have a source for any of this.

No, I don't think they would. I've never heard of Vaughan and assumed one syllable like the parent commenter.

No, "gh" is usually silent in English spelling.

augh is not as common as ough, but either one can make any sound in the whole syllabary.

How about Sequim, WA. Guess how to pronounciate that.

Or Puyallup, WA. Those two are definite shibboleth tests in the PNW.

Pend Oreille is the eastern WA test for western WA.

and for our eastern neighbours: Coeur d'Alene, Idaho (and Boise too)

My years of french class steered me wrong there.

Des Moines, WA vs Des Moines, IA.

Laugh, trough, tough, rough. Maybe it should be "Vawfan"

Ghoul.

Hiccough.

Loughborough, which has it both ways. (Apocryphally pronounced by Australians as "Loogahbaroogah".)

There are a handful of neighborhood and street names used in Toronto (not necessarily from Toronto) that have unusual pronunciations. Here I'll give some triples of (English spelling, actual pronunciation (IPA), a naive pronunciation (IPA)):

(Yonge, [jʌŋ], [jɑndʒ]); (Strachan, [sdʒɹɑn], [ˈsdʒɹa.tʃæn]); (Tecumseth, [tə.ˈkʌm.zi], [ˈti.kəm.sɛθ]); (Markham, [ˈmɑr.kʌm], [ˈmɑrk.hæm]), (Etobicoke, [ɛ.ˈtoʊ.bɪ.koʊ], [ɛ.ˈtoʊ.bɪ.koʊk]).

See also: https://www.youtube.com/watch?v=i2cyg6bFeRc , https://www.youtube.com/watch?v=1PmeDWvwD8M

That's because some are Indigenous names phoneticized for English speakers (Yonge and Markham on the other hand are entirely English names):

Etobicoke. From Adobigok [1]

Tecumseh (or Tecumseth). From tecumtha or takhamehse [2]

Mississauga. From Misi-zaagiing [3]

[1] https://www.etobicokehistorical.com/brief-history-of-etobico...

[2] https://en.wikipedia.org/wiki/Tecumseh

[3] https://en.wikipedia.org/wiki/Mississauga

As a non-native English speaker I wonder if Leicester is naturally pronounced right for the natives, or has to be explicitly taught.

It has to be taught. Most english native speakers will say Lie-chester by default.

Typical in Toronto - remember there’s only one T in “Toronto”

There's also only one T in "Atlanta". (For some people there are none.)

Definitely heard "Alana" in the South. On the West cost right now, got a buddy from West Virginia, and even after 20-30-some-odd-years in California, he still says it like that. Among other things he boomhauers.

I didn't realize "boomhauer" could be verbed.

...and the first o is silent, and the remaining o's are pronounced 'a'.

But the TV news reporters enunciate every letter in Toronto.

ROFL. I ignore this sacred rule

'oronto?

Asking people how to pronounce "Strachan Street" is an old Toronto pastime. (Strawn, by the way.)