Okay, so my interpretation is this...
The protagonists of this story are two people in 'love.' Outwardly they do all the things that appear to be love, and they are, for all intents and purposes, functioning within this. It is, however, formulaic -- a calculation. The song is about the decision that people make to open up (make an incision) and delve into a deeper, riskier place in hope of a greater experience of love. These characters find that inside, their hearts had withered from lack of use -- the macaroni computer has made them redundant-- so they resuscitate their emotional lives by physically creating sparks like with flint and steel.
Okay, so my interpretation is this... The protagonists of this story are two people in 'love.' Outwardly they do all the things that appear to be love, and they are, for all intents and purposes, functioning within this. It is, however, formulaic -- a calculation. The song is about the decision that people make to open up (make an incision) and delve into a deeper, riskier place in hope of a greater experience of love. These characters find that inside, their hearts had withered from lack of use -- the macaroni computer has made them redundant-- so they resuscitate their emotional lives by physically creating sparks like with flint and steel.