Thanks for that, John.
But is that not the function of the style.css file of a child theme?
Often, even when using a child theme, I find myself having to use !important because that is the only way to override some plugin CSS. Would your solution prevent that?
I guess using CSS specificity would also fix that.
[and for those who wonder what that means, I found this explains it quickly:
http://www.htmldog.com/guides/css/intermediate/specificity/ ]