VERY useful. Thank you for taking the time to put it together.
On TF 8666... the description is a bit unremarkable as to what it can actually be used for. For example, one of the things that it causes to be included in execution plans are the names of the stats it used to come up with the plan. Using a bit o' XML magic and over time, it allows you to clearly identify which stats are actually in use so that you can delete unused stats.
Jeff, great thanks for your answer, added to github. Be free to add pull request or just post a new comment.
I cannot take the credit for it. The man in the following article deserves the credit. It's a fantastic article if you're having problems with too many stats and need to find what they are.
https://blogfabiano.com/2012/07/03/statistics-used-in-a-cached-query-plan/