Hahaha I'm the Dave and I really enjoyed your argument about it!
It's a string, indeed, a very thin transparent wire (used for fishing, as wana said). What you do see in this pic, is where I broadened it with scotch tape so it doesn't cut my already abused knuckles. Pretty sucky method but the timetables were my last minute prop and the shittiest thing I've ever done.
cheap pieces of shit, man