Raynn
Coroner
Having used one of those razor wire saws, at the age of the character, I have no problem seeing that as possible or plausible. Seriously, I went through a log in nothing flat, just for kicks. It's supposed to make things that easy.
Yeah, but is a guitar string a razor wire saw? I used to play guitar and I can tell you, those metal strings I had, nowhere near sharp enough to cut through muscle and bone. I get that the show has to have a little dramatic license though...
She used the strings to tie him up. There was a proper wire saw in the garage (Nick found it), that she used to cut him up.
I don't find the physical effort that unbelievable. The wire saw would've made the dismemberment pretty easy (much easier than a fruit knife!). Moving the body wouldn't have required lifting the full weight, as she dragged him to the bathroom, and then could've lifted/dragged him into the tub a bit at a time (just the legs over the edge, then lift the torso to follow).
I find it very disturbing that she had absolutely no sense of how wrong what she did was.