If you ever have a document with
huge chunks of repeated text that you need to delete, just use the search
and replace function (Crtl + H) to replace this text with nothing.
Just copy the "offending" text into the "Find" field and leave the "Replace"
This can be useful for removing all sorts
of things. For example, when pasting from older versions of Netscape,
the result was that you often carried blocks of spaces into the final document.
This would delete most of that. Similarly, I have used it to replace
chunks of HTML code (e.g., "</b>") that sometimes show up in my documents
as well as removing the numbers from numbered lists.
Note that you should take care to ensure
that you are not going to delete any text that you *do* want to keep.