help, xdf-S11-T21 , sentence structure and meaning

isuffering

21. The filibuster, a parliamentary device that slows the
snail's pace that prevails even in the best of times in
congressional sessions and tests the endurance of
everyone associated with it, seems more and more
an anachronism in the age of telecommunications.

I'm not sure about the meaning and the structure of the ",..., " part of the sentence.

here, is the structure

, a parliamentary device
that slows (the snail's pace that prevails even in the best of times in congressional sessions )
and tests( the endurance of everyone associated with it),

i.e.
a parliamentary device that slows and tests

or

, a parliamentary device that slows the snail's pace
that prevails( even in the best of times in congressional sessions)
and tests( the endurance of everyone associated with it),

i.e.
the snail's pace that prevails and tests


Can anyone help analyze the structure and give the meaning of the ",...,"part of the sentence ?

Thanks in advance.

xink

我觉的是第一种。

a parliamentary device that slows and tests

isuffering

xink, thank u, but
can you explain why?

[此贴子已经被作者于2003-8-1 10:07:21编辑过]