Yep they can be handy. I keep a tin knife in my Tilley hat.
For the love of God though Pitdog, please tell met that isn't crappy yellow polypropylene twine on your kit knife! Uhg - I hate that stuff. Inevitably some damn student always brings a bundle of that crap on my boat. It is absolutely useless and should all be melted down to make plastic grocery bags to further pollute our forests!
Recognizing that paracord is too big for a tin knife, what about some of this nice reflective yellow guy-line sold at CDN Tire for 5% a 50' length in the camping accessories section. It is pretty decent and about 1/2 the diameter of paracord.