There used to be an "orifice" in the hard line on 03/early 04 models, but was removed from later models.
That sounds like what that place was trying to describe.
Here's the 03 clutch piping, I think people used to drill them out:
Do some more research before you try to start replacing things. A simple fluid flush goes a long way on these cars. A clutch pedal mod will probably also to fix what you feel is sluggish, I use the RJM AFP pedal for example, others simply remove the helper spring.