[WikiEN-l] Citation categories?

[SPUI]

A while ago I was reading an article about something in Texas and came 
across http://en.wikipedia.org/wiki/Category:Handbook_of_Texas_citations 
on the bottom. That category is added by 
http://en.wikipedia.org/wiki/Template:Handbookoftexas , a useful 
external link template. But the category seems like simple clutter in 
the list of categories on the article. So I listed it for deletion ( 
http://en.wikipedia.org/wiki/Wikipedia:Categories_for_deletion/Log/2005_September_23#Category:Handbook_of_Texas_citations 
). Due at least in part to someone spamming the talk pages of Texas 
Wikipedians, the category was kept.

I honestly don't understand any of the arguments for keep. Some are 
plain erroneous (one person likens it to 
http://en.wikipedia.org/wiki/Category:1911_Britannica , which is for 
articles that *contain* text from the 1911 EB) and others don't make sense.

Basically I'm asking for a reason why this category should exist, and 
why I shouldn't be bold and remove it from the template.