If I'm trapping in a creek with a muddy bank, I'll set my 1 1/2s by hand, wearing gloves usually.
Stronger coyote traps, sometimes my gloved hands, but mostly my feet.
If you want to know how to set a coilspring with your hands, watch the "Destroying the Myth" video, there's a beaver trapper on there that does it really fast. (that's where I learned, anyway!)
As far as breaking or incurring damage, never had a problem.
Scent contamination? If I set with my feet, my boots smell more natural than the coyotes do by the time I get to the set, and under water it dosn't matter.
I'm only using Coilsprings, but I do have two #3LS, which I set over my thigh.