Pool and Cluster tables

Hello,

Why do we use pooled and cluster tables?

I have heard that these logical tables came about as the consequence of a historical limitation on the number of columns possible for a single table (I believe the restriction was 255).

I have checked tables contained in table pool KAPOL for example and found that the tables contained did not have 255 rows anyway.

Why not just simply define all of the pool and cluster tables as transparent tables?

Is there any merit to using logical tables?

Kind regards,

Peter Strauss