"The idea of linking up with Sean was to get back to swinging the way I used to," Westwood told reporters.
"I finished with Pete Cowen last August and after so long without a coach I felt I was getting a bit out of synch. So, a couple of weeks ago we had a five-hour session that went really well.
"We spent most of the time working on my posture and my position at address and I feel like I'm hitting the ball a lot better. I'm definitely hitting it a lot further."
Westwood, currently ranked world number 12, has finished in the top three of all four Majors.