I played in my first Club Nationals in the Open division and it was great. It was also the first trip for my team (including 26/27 members) and we finished 13th (out of 16).
I've heard that playing at Nationals somehow drastically improves the game of you and your team, and I guess that's true. The long term effect on Madcow is yet to be seen, but I think my game has been improving. I think that started at Regionals however.
As a rookie, Regionals was understandably a pretty nervous event for me, but by the end of it I found a comfort zone. I didn't play amazingly, but I did gain some confidence. During Nationals, I again faced a little nervousness (who wouldn't?) but I soon realized that I had control over my play. Almost all of the teams we played were at the same level as the guys I practice against all the time. The guy guarding me might be a little better or worse than average, but it's still the same game. If I run hard no one is going to shut me down.
I think the magic of Nationals is that each game matters as much as the last and each game requires the same amount of effort. And, each game feels very meaningful. And it happens over a longer time-span (3 days). It gets you into a groove of playing competitive ultimate that irons out the inconsistencies in your game. Of course, I don't think that's too different from someone playing in their first college tournament, but that's why that first college tourney can also be a big step in someone's game.
In the end, it's not that a new competitive experience gives you new skills, but rather it brings you mentally to a new level of play, and you see new possibilities in your game.
