Webpage Title Tags

[alfuzzy]

I've been reading about Webpage title tags...and two things that are almost always mentioned are:

- Each web page should have it own title tag.
- Each web page should have a unique title tag.

When it comes to vBulletin websites...I've been told that you only need to enter a title tag once & only once in the head or headinclude template.

Thus the question is:

If it's good practice for each web page to have its own title tag & that each title tag for each web page is unique...how does entering a title tag only once in the vBulletin headinclude template optimize the use of webpage title tags?

Thanks