It always seemed fairly obvious to me that he would have taken the name Springfield from the town by his own hometown, but I think the question of where he got the name in the real world and the reality of the location within The Simpsons universe as not necessarily related.

Still, the Smithsonian interview was fun to read, and I didn't realize it was out (or even that it was coming), so thanks for posting.

so this is nothing new.

Of course it doesn't really work. If you try to place Springfield based on events and references on the show, you end up with a bunch of contradictions.

I've also heard besides Father Knows Best that Dan Castellaneta said in an interview that the original inspiration for Homer drew from Odd Couple era Walter Matthau. And then all the characters that look like Homer - Krusty, Grampa, and so on are different variants of that character.