Improve Ubuntu internet speed...safe?

[fifth_rune]

http://www.ubuntu-unleashed.com/2008/05/howto-tweak-your-internet-connection.html

This has a series of terminal commands in order to tweak your system to make it faster/more responsive but I haven't tried it yet. Anybody with some knowledge of this sort of thing can you verify if this is safe?

[chucky chuckaluck]

it looks like it's easily done and undone.

[insane_alien]

this should work fine. if you get issues with it, open up sysctl again and delete the lines you added. you can mark them with comments if you want.