For various reasons, I'm planning to use a combo sliding dovetail/dado joint to attach the rails to the sides of a chest I am making. Dovetails for the ends of the rails and dadoes for the drawer runners.

My question - would an 1/8" depth for the dovetail do anything, or should I make it 1/4"? Since these are all sliding in from the back, the dado and dovetail depth needs to be the same.

Thanks and I hope my description was clear enough!