Haha 3 Plantagenets are nothing. I just got through merging 20+ duplicate Henry Adams and John Adams of MA, though there's still a few differences left to be resolved, and the bio is still a work in progress. When I finish the merges I then merge the biography/source sections (it would be nice if these sections were merged in the right order automatically, but that would require parsing the words properly).
On long profiles I provide first a quick summary paragraph. Next all of the firsthand references/sources, in chronological order (parents, birth, childhood, marriage, children, death). Next all of the sources merged together in a list, with all of the 'noise' removed, i.e. a single ancestry.com or oneworldtree link, no comments or 'click here' or 'created by'. I leave ancestry info in place but merged down to a single non-duplicate link, so that we at least know the info originally came from ancestry.com even though we can't view the info. I put those at the bottom of the sources. Any sources with specific firsthand knowledge (census, birth/death/will records) or links to sites with firsthand sources, I put first in the sources list, with a comment about the info contained if not obvious from the website name. Next I add <references/>. After that, I move 'created by' 'imported by' 'firsthand knowledge' info to the bottom of the page, in the order of creation. I believe that the profile history info is still relevant, but probably the last thing that profile reviewers want to look at, thus at the bottom. I try not to duplicate biographical info available elsewhere, linking instead.