Poor race organization. There was clearly an issue with course direction prior to the start when the announcer was confused by what the runners should follow and simply said "there will be plenty of volunteers to direct you". However, there was a mistake in the course where the top runners were misdirected. Interestingly, I was taken off course following pacers and cyclists who were officially involved with the race and not other racers. I also read in the newspaper today that the race director took absolutely no responsibility and blamed the RUNNERS for not knowing the course. I have been in an uncountable number of races and have never once had to memorize a route in order to successfully complete the race. That was poor taste for the race director to not simply apologize for the issue.
Better on course direction and new race director. Don't blame runners for the organizers ineptitude.