Cloak of Displacement vs. Ring of Blinking

[James McMurray]

You mean all sneak attacks, 80% of the time.

Nope, they're all sneak attacks, some of them just might miss.

Ah well, and then there's the interpretation that this miss chance means you can't sneak attack

That would be a bad interpretation. Concealment stops sneak attacks, but Blink is not concealment.