If they are twin tube shocks, like Raunchos, then they really need to be mounted body down. Rauncho used to say that you could mount their 9k's either way. They don't say that any more, and THAT is where the confusion came from. Mounted body up puts some of the body mounted valving in the gas and not in the fluid. they don't work so well that way.
With mono-tube shocks, like Bils, SAW's, Fox's, etc. you CAN mount them either body up or body down. In these shocks all of the valving is on the piston.
I have always run my Rancho's body up and have never expericenced any of these issues. From out of the 6 rigs I have had them on I broke only one at the welds other than that one I've taken them on and off the trucks, in fact the pair on the rear of my current truck came off of my Willys and before that they were on my Sammi, they are just as good as the day I bought them. The pair on the front came off a full-size Ramcharger that I owned and never had any problems running them body up or down. I run my rear body down and my fronts body up only because I lazy and don't want to climb under the front to adjust them.