I've been shot in the stomach by a guy who failed to chrono in his 98. It was shooting darn near 500 fps. Left a nasty bleeding welt that did not fade entirely until four whole months had passed. I've also seen images of people whose eyes have been hit by paintballs. I'm pretty sure I know all about how "unsafe" a paintball can be.
However, if everyone is chronoed in to 300fps or lower, which is the speed at which the masks are rated to handle, and are wearing said masks, I don't really see anything unsafe here. I never once suggested that people intentionally bonus ball each other, but if you are shooting off a rope and someone walks into it... they're going to get lit the heck up.
If our sport was so unsafe, many more people would be hurt on a regular basis, by paintballs, and hardly any local field would be able to operate simply due to costs of insurance.
Instead, data shows that you're more likely to sprain an ankle or fall and hurt yourself than be actually injured by a paintball, provided that everyone chronoes in and wears a mask. Sure, sometimes you welt up, but I'd hardly call that lasting permanent damage.