That is 100% the way a site should be run.
So many people get reporting wrong, and worry about rankings all day long. Julie's way is absolutely the best way to measure a site's performance. Who cares what your rankings are if people don't buy anything, and even without a rankings boost, many people can improve conversions rates and the bottom line.
Optimising a site is about making it better; constantly better, in every way. Focussing on real metrics is far more productive than looking at rubbishy ones like rankings, and what is better, if you otimise for better conversions, you make more money to spend in the long term on SEO and driving traffic, which now converts better etc etc.
Great post Julie