Does placing 
said before or after attribution – as in Thales said or said Thales – matter?
The answer in large part depends upon how it sounds in particular sentence. Given that, how a reader responds really is a matter of personal taste.
Still – and this is grounded solely in my training as a journalist – I almost always place said after the name. That’s because said is a largely invisible word that readers just need to spot, rather than actually read, to make a sense of a sentence. What’s important in dialogue, of course, isn’t said (the quotation marks show that someone was speaking) but who said it. So readability can be improved if the name is given right after the quotation marks and said is relegated to after the name, as in Thales said. The eye then can naturally flow from the speaker’s name to the next sentence.
I have yet to see any scientific evidence proving this theory taught by some journalism professors and practiced by some editors. Regardless, if most American newspapers and magazine articles follow this pattern, then most American readers likely are unconsciously comfortable with the construction. Further, with the advent of the Internet, people tend to scan text rather than read it as they would a book, meaning readers probably will prefer any writing that improves their scanning efficiency.
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