Hoart Petterson said:
There is an "aww" in dawn. If there wasn't it wouldn't be spelled with a W. Dawwwwwwwwn. Dahhhhhhhhhn. Awwww, look at the dawn. Don, open up and say ahhhh. Say it out loud "awww"...now say "ahhh". Back and forth. See what your mouth/face is doing? They are nowhere near the same sounds. There is no accent, no strange additions, only the way the words are meant to be said. Maryanne and Ralph Furley did a Love Boat once. When the director called out for MaryAnne (Dawn Wells) did Ol' RF (Don Knotts) turn around too? Only if he was almost deaf which is entirely possible. If he wasn't, he wouldn't have turned around and would have kept gazing into the fake ocean.
I know you said you pronounce Don like Dahn. I don't know how much you overpronounce the aw in Dawn. If you pronounce it like Aaron, you're pronouncing it like I say Don. If you pronounce it like a New Yorker, then you say Doe-uhn, and both of your pronunciations for Dawn and Don are different from my Don, which is identical to my Dawn. The important thing to realize is that, in all of these scenarios, we're busily talking about which accent you use, and trying to understand the confusion people might have because of that accent, or the confusion you would have because you believe that your accent, and not Aaron's, or Otis', or Ignoratio's, or the homeless volunteer from freedictionary.com, is the right one. My Don and Dawn don't cause confusion, except among people like you who choose to make them sound different from one another. Your choice to make the words sound that way is causing you difficulty. I don't see how that's a compelling reason for me to think that this is proper English.