this isn't a spoonerism but a fully-fledged insult in its own right. it should be used in pleasant company as a derogative term favouring the speaker and referring to the audience. whilst there is a passing similarity to words spoken by Linda Blair, the referential difference is clearly important. it is a calm approach to dissing, using only references to items of clothing and common actions (normally using scissors).
"I love you!"
"SO! Your mother cuts socks in hell"
"Damn right she does"
"I love your too!"
(loud audience applause)...
(shouted by band member on stage)... "Your mother cuts socks in hell"
(louder audience applause)...