This is the number of views that you can test each month on your website.It's up to you how you choose to use them, either by allocating all the views to one test or to multiple test, either on one page or on multiple pages. If you have selected the 10.000 tested views plan and you run an experiment on your category page which is viewed 7000 times per month, then at the end of the month 7000 is what you'll be counted as tested views quota.
That’s true Thomas – this can happen when going after very competitive keywords. To avoid that you can just grab the first subpage you see ranking – subpages most of the time won’t have a lot of brand searches associated with them/you’ll see true topic value. It may be lower than normal, but in general can’t hurt to have a passive calculation when making arguments of what you might achieve.