The take-aways?

There are 4 key, valuable lessons that we can learn from David's research.

1. Be methodical, working through each of your possible candidates one by one.

2. Keep in mind the goal of eliminating all possible candidates, and then looking in greater depth at those that remain.

3. Explore wider record collections for further clues if needed.

4. Usually we are advised to trace backwards in time, but sometimes it pays to trace collateral branches of your tree forward in time.