Did 4 sets of 500 yards broken up by a 200 yards of breaststroke.
That last set is 2:30/100 yards. That's barely faster than I swam at Eagleman Half Ironman - but much slower than I swam at Columbia Olympic distance (34:07 for 1500m/1640 yards). I'm hoping to swim somewhere close to 34 minutes at my two Olympic triathlons in September (Annapolis and Walt Disney World), but if I give up a minute or two it won't surprise me a bit, especially if we can't wear wetsuits!
I think the slowdown that I get in sighting in open water swimming just about breaks even with the slowdown I get from doing open turns in a pool. Maybe I can pick up some speed by drafting! The Annapolis swim should be fun, right at the entrance to Ego Alley and next to the United States Naval Academy. At least we should be able to check out some nice boats while we swim.