Be prepared to swim over others, or be swum over...it can get almost combative. And if it's open water, breathing so you can look straight ahead about every 5th stroke can be quite helpful.
Pool swim, one at a time every 5 seconds, which seems close enough to a mass start. At the end of each lap, touch wall and then duck under lane line and push off. I think that 8 minutes should start me in the top 25, and then I need to keep up my end of the bargain. :)
Nice. That's a bit less shocking than everyone swimming over the top of each other on a lake (my first was in Lewis Lake at Ft. Lewis). Easy to stay straight, too.