[quote=akje]
can you support that? link to source?The other point was that there wasn't really anything holding the net in place. If I run at full speed at a bedsheet suspended from a clothesline the question isn't if I run in with enough force to rip trough it, won't happen.I'll just take the thing with me wont I?
[/quote]

Monofilament wire is a fictional wire that appears in a variety of movies and novels, including Hellsing and several other works of literature and animation. It's not real, if that's what you're asking.
Now, if you were to run full force into a katana, the katana would be so sharp that your body would be cut to shreds. If you have a really sharp knife, you won't be able to exert any real force on it due to the fact that the edge is so thin.