Is 'bouncing' an airliner on landing in high winds a deliberate technique, or something always unexpected? Last week, 767 landing at Newark, high winds, a good deal of rocking in the last few minutes, some passengers quite distressed. The landing was harder and noisier than usual, and we immediately floated upwards, must have been a couple of seconds before we landed again.

The question I have is - in these circumstances (high winds), would the pilots have been flying the landing with a little less flare than usual and anticipating the bounce as a way of shrugging off some speed / energy; or, is it something you never quite know if it's going to happen or not, and would rather didn't happen at all?
Bouncing a landing is neither intentional nor desirable. There are several reasons why a student pilot might bounce, but for a professional pilot, it's most likely related to wind gusts, which are a challenge no matter how much training and experience you have.

Gusts are by their nature unpredictable, and if one hits the plane right as it's touching down, it can suddenly lurch upward and/or downward, resulting in a bounce. That's probably also why your plane was "rocking" before landing.