sga_target setting

 I just started using the automated sga management with the setting of sga_target. I read some of the articles recommends comment out the following settings (db_cache_size, shared_pool_size, large_pool_size, java_pool_size, and streams_pool_size) so that the sga will decide for itself. I also read some other articles says that we should still set those parameters as minimum value. Now, I am starting to get confused. Which way should I follow? Can anyone shed some light? Thanks.