Hey Budy -
95% of the time Tableau Server does not need to be optimized. If a workbook is "slow" on the Server, you're almost always looking at an authoring issue vs. a configuration change that you make to the server which suddently makes the workbook fast.
I'd bet that you come from a legacy BI background (like I did), where you almost always need to tune your server in order to get good performance. Tableau isn't really like that. Nearly all of the default configuration options are good places to start and should not be modified unless you are trying to solve a specific problem.
FYI, the -o command really is just a quick way to get a dump of all of the config settings on a box - nearly all of these settings are internal to Tableau and things that you would never touch.
That said, are you running into a specific problem, or just curious?