This post tests comments in the following ways.
Threaded comments up to 10 levels deep
Paginated comments (set Settings > Discussion > Break comments into pages to 5 top level comments per page)
Comment markup / formatting
Comment images
Comment videos
Author comments
Gravatars and default fallbacks
This post has its comments, pingbacks, and trackbacks disabled.
There should be no comment reply form, but should display pingbacks and trackbacks.
This post has many pingpacks and trackbacks.
There are a few ways to list them.
Above the comments
Below the comments
Included within the normal flow of comments
This post has many tags.