Is this a good definition for clustering factor

Hi List after googling I formulated this definition, is tihs right, or I missed some point, thanks.

Clustering Factor

The clustering factor is used by the optimizer when a large number of data is gathered.
When an index can be used to access data, Oracle looks the clustering factor information on the index.
This Clustering factor tells oracle, how much blocks will need to be read to get the data required by the query condition. If to get data, oracle is going to read almost al the table, then the optimizer choose a full table scan without using the index.

A high clustering factor means more blocks needed to read data because the value on that field(s) are spread across several database blocks, and conversely a low clustering factor means the value on that field(s) are spread in few database blocks.

The value stored in the clustering factor is a counter, registering the number of times the index pointed to another table block when the index was scaned in order.

When the number of rows is higher then the number of blocks. If the count is close to the number of blocks, then the table is ordered according to the index.
(index entries in a given leaf block point to the same block )

If the count is close to the number of rows, then the table is NOT ordered according to the index.
(index entries in a given leaf block point to different blocks)

Clustering factor is present in DBA_INDEXES, DBA_IND_PARTITIONS and DBA_IND_SUBPARTITIONS view.

Tuning.
Rebuild a index only because is has a high clustering factor is useless, because the reason for the high clustering factor is the order of the table, and the only way to change it, is changing the index or the order of the data in the table (or the way the data is stored in the table).
You will have to decide the best order in the table based on the index you have.

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