Can Views theme/rendering be disabled programmatically? I'm creating an RSS feed using the default Views RSS display and by default it contains a bunch of characters that cause the output to be invalid XML  (I believe this has to do with bugs within views related to double encoding or other related functions).  

So, to fix this, during hook_views_pre_render() I am able to manipulate the fields with php to output valid stuff.  Within views when I "preview" the output, it's exactly as it should be.

However, when I view the actual feed output at the views url, the output has changed because views has done something to render it (I'm assuming putting it thru the theme system, etc), thereby breaking my 'fixes' again.

Manipulation of the fields in the UI (ie. using plain text as the output, etc) don't do what i need, so those aren't an option.

Is there a way, programmatically, to disable any rendering and tell views to output exactly what I'm seeing in the Views preview?
Yes under Advanced there is a Theme Information link that will show you template file(s) that you can override to meet your needs depending on the display format selected (fields, rendered entity, etc).

If you need to change how the page itself renders for example, you can also affect the sitewide theme function used to create the url by changing theme function in hook_menu.