I’ve never done a practice for an event on the actual course in advance of the event. But, there are a couple sayings, or ‘practices’ that come to mind here. One is: “Practice like you play.” IOW, do the practice swim like you’ll be swimming the actual event. The other is: Don’t ever use new equipment for the first time in an actual race. So, if you haven’t actually used the tri suit yet, I’d certainly get a swim or two in it (not necessarily on the racecourse)…as well as wearing it on a ride and a run. It’d be very frustrating if you find out on the bike, or in the run, that it chafes you, or doesn’t fit comfortably for that activity. But…if you’ve worn the tri suit, and are comfortable with it…then swimming in jammers just to get familiar with the course is fine. Things to look for on the swim: If it’s a body of water with currents/tides, take note of when, where, and direction of flow. (If it’s in water affected by tides, check the tide tables for that location in advance of the race). Look for shallow areas that might be too shallow for swimming at a low tide. Look for places where swimmers get congested, and how you might avoid that. Check prevailing winds, or wind forecast for race day, and look at where on the course you’ll be swimming against the wind. The difference in the water conditions swimming with or against the wind can be VERY different. Footing at the water exit, and along the path to T1. I’ve actually had flip-flop slides staged at the water’s edge so that I could run while others had to walk over the sharp gravel.

Dan