Well, actually, as is the case in military after-action analysis, assessing screw ups can save lives in the future.
As my namesake wrote 21 centuries ago:
".........there are two ways by which all men may reform themselves, either by learning from their own errors or from those of others; the former makes a more striking demonstration, the latter a less painful one."
In the event that you have a friend going to put up a circus tent, by all means, warn them.
I'd hate to think a family member or friend of these folks would cruise through this thread and read some of the comments made on it.
This is a time for sympathy, not explaining what a foolhardy thing these men did.