[wp-hackers] checking the nested categories one by one

[IC IC]

Hi guys,
What is your take on the following two different scenarios?

You are on the admin dashboard and associating a post with a category,
in this example beverly hills.

And here the (+) indicates the check mark

scenario 1

...usa
......ca
..........los angeles
...........+..beverly hills
...uk
...china

vs scenario 2


+..usa
...+...ca
.......+...los angeles
...........+..beverly hills
...uk
...china

When associating your post with BH, you have the option of checking
either only BH  or going all the way up in the BH's hierarchy and
ending up checking us, ca, los angeles and BH.

Of course, there is the in between options such as checking US,
skipping CA, then checking LA and BH.

What are the back-end implications in between these options?
It looks like most themes, ( 2011 for one) treat it as if you checked
them all - even if you were to check only BH. That is when you browse
yje US category, you do see the post for BH. Sure;y it is convenient
for the user but what about performance?

Isn't it more taxing to SQL to pull all posts associated with not only
the current cat but all children down the road?
Isn't it performance wise, much faster to query "give me all posts
that are associated with the *this* category and not its children?

What's your take on that?

Of course this question would be not complete if I did not mention
that you are running a heavy traffic magazine/news styled web site and
not a simple blog.