From the server resource allocation perspective is there a difference between these two statements:

This is a Data warehouse with many large fact tables and many smallish dimensions.

My understanding is that smaller tables should not use parallel processing.

I have also read that if parallel is set to ie.

ALTER TABLE table_name PARALLEL (DEGREE 1 INSTANCES 1);

Oracle will assign a coordinator and a parallel process.

However if parallel is set to ie.

ALTER TABLE table_name NOPARALLEL;

Oracle will not assign a coordinator and will process in serial.

First is my understanding correct and is there any other difference in resource allocation?