Safe Jack Stand Usage

So I thought I'd rotate my tires today as I was replacing the brake pads. I picked up a second set of jack stands, but as I was unpacking them I noticed a warning on the side that basically said even thinking about using jack stands to support more than one end of the vehicle at a time would doom three generations of your family to always having their bread land butter side down...

Is this just the manufacturer covering their :eek: , or are there certain dangers/precautions/steps to doing this I don't know about?

Thanks!
L.

I have always heard it is bad to use the stands to support the whole vehicle. I recommend buy a set of four for someone you do not like and asking them to try it out for you. Either way it is win/win for you because if it works you know you can do it but if it fails, well there is one less person you do not like bothering you.