Currently the edit conflict simulation special page included in the TwoColConflict extension only offers a rendered preview of the text that would be saved. A diff page that can be reached from conflict resolution page would make it easier to spot the applied changes though.
BDD definitions
Given I am on the edit conflict simulation page
When I click on "Show changes"
Then I see a diff of the article above the resolution screen
And the page is scrolled up to the diff.