I think all the reasons have been stated already. But I'd echo them.

I enjoy sailing solo - sail when you want to, go where you want to (events). A major benefit is not being able to pass the buck - I know that any improvement has to come from me.

The smaller / lighter boat just makes the whole thing practical. There's no less sensation of speed, and in fact I think the thrill increases as the boat size reduces. The more I sail the Shadow (solo), the more I love it - it is so responsive, and as a solo sailor you can really become a unit of "man and machine". The Shadow can beat with the best of them (well, maybe not the A Cat), and gives helluva ride downwind in a blow, trapezing with the kite up.

And if we all did it, there'd be twice as many boats at regattas <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />