For me it's about the aesthetics. That's the way the cars were when I was a kid totally obsessed with racing. By the time I was old enough to get involved in racing in the later 60s and then on through into the early 90s everything had to have a cage on it. I've never built, driven or wrenched on anything that didn't so I'll leave the "bravery" disscussion to guys like Denny Z. and Spike Ruth (if he's still with us). To my eye, though, a pure, classic open wheel race car doesn't have a roll cage, and perferably, even a roll bar for that matter.