Somewhat agreed - but I also think a lot of it was Nixon knew he was checkmated, and it was less propriety, and more just plain ol' shame and knowing he had no recourse. I imagine he was not alone in his deliberations, though, and that his advisers - particularly his legal advisers - agreed.

I recently read "The Brethren" by Bob Woodward and and Scott Armstrong (http://www.amazon.com/The-Brethren-Inside-Supreme-Court/dp/0...), about the Supreme Court from 1969 to 1975. Watergate is a major episode, and it shows that Nixon knew that if they lost their Supreme Court appeal (https://en.wikipedia.org/wiki/United_States_v._Nixon), there was little recourse left.