The theory is that topic is related to DMOZ (and by extension, Google's directory), so if the site is listed in the ODP, the topic is the category.
I have to disagree with this logic. It is not likely that Google determines the topic of a page based on the listing in ODP. It is likely that Google uses ODP to determine many topics and how they are ordered.
In my opinion a page may fit in more than one topic/subtopic. Especially in subtopics.
For instance a page about cars that describes 3 brands of cars fits in the topic/subtopic of each of these brands, in the topic cars,.. perhaps even in the subtopic car reviews, etc. etc. etc.
Determining the topic(s) of a page is not as simple as just simply copying the ODP structure and see where it is placed. That would not be very Google,..
Then it seems that it is not possible to rank high for a higher level topic. If the page fits in a subtopic,. it won't rank high for higher level topics. For example a page about knitted sweaters, won't rank high for sweaters because knitted sweaters is a subtopic of sweaters,.. and to be fair,. knitted sweaters is NOT related to sweaters. The opposite is true though,.. sweaters is related to knitted sweaters. (knitted is not by definition a property of sweaters, but it is by definition a property of knitted sweaters).
So when you target a certain phrase, you have to be careful not to accidentally target a subtopic. Example,.. Alabama web designer,.... if that is in your title,. and in your description and in your header tags,. you can forget about ranking high for web designer. You will rank good for Alabama web designer though. Alabama web designer is a subtopic of web designer.
Of course this all is just my opinion. I could show you examples that this is correct, but there are many people that can show examples that it is not correct. However,. It is still my opinion,. .
Regards,
Peter
