Here's an odd one that I'm curious about...Today I traveled EWR-MCO. It was snowing and we got de-iced prior to take off. Just as we were about to turn onto the runway for takeoff the pilot revved the engines up fairly high for at least 20 seconds with the brakes on. It just seemed very unusual and the last time I heard that was years ago in IAH and we were stuck in the mud after rounding a turn too tight. As the engines came down you could feel the brakes release and we turned on to the runway. Just curious if any experts out there would know why they did this. Some sort of check?

Thanks,