What do the following phrases have in common?

TURNS TO STONE
THE SCARLET LETTER
SHOW HOW IT'S DONE
PAINT INTO A CORNER
SIMPLE PLEASURES
LESS ESSENTIAL
GIANT ANTEATER

HINT:
It has nothing to do with the meaning of the phrases or their relationships to each other.

Answer:

Each phrase has two sequences of the same three letters:

turnS TO STOne 
the scarLET LETter.........etc. 

Credit: NY Times Crossword
May 13, 2007
Jim Page
TWO TIMES THREE