Today we won't go into the difference between breeches and britches, but we will mention that breeches are pants (or if you like, pantaloons) that cover the, um, posterior. Today that's true of most if not all pants.
What then, are double breeches? In terms of pants, we can't really say, but our Research Department did point out that the word breeches is what's known as a double plural. In old English, broc was a word which had a plural form of brec. In time the word evolved and added the usual -(e)s suffix and thus became the double plural, breeches.
If that's just a bit too complicated, fortunately in checkers double breeches has a very specific and easy to understand meaning, as you'll see in Bill Salot's 62nd World Championship Problem Composing Contest, which has double breeches as its theme. Access the contest problems here.
To get you started, here's a sample problem illustrating the contest theme. It's by grandmaster composer Ed Atkinson and was the winner of Contest 33 in June, 2017.
After you've enjoyed solving this problem, click on Read More to see the solution, and then go to the contest page to cast your vote for your favorite among four additional problems.
*10 7---A, 9-13---B, *7 3, 13-22, *3 7, 11-16, *7 11, 15 8, *24 19 Double Breeches, Draw.
A---Not 10 6, 15-10 (best), 6 1, *11-15, 17 13, *23-19, Black Wins.
B---If 23-19, *24 20, 9-13 (15-10, *17 13 Draws), *7 3, 13-22, *3 7, 19-16, *2 6, Draws.