Is there a way to show a node's comments when displayed in teaser format on the taxonomy term page?
Associate a custom node to each taxonomy term.


Create a content type of "taxonomy term page" with comments enabled.
Add a custom field of type "taxonomy term".
Create a View, with a display of type block. Add to it a contextual argument of type taxonomy, and specify from where in the URL path is the argument going to be found. This should filter out nodes based on the current taxonomy found in the URL path. For safety, add a content type filter (regular, non-contextual), and specify "taxonomy term page".
Change the render type from "fields" to "node", or something like that. Try to see if in the node display option, you can choose to render comments as well.
Using Context, add a condition for taxonomy/term/* paths.
In the same Context, add a reaction of type block. Browse and select your block. Add it to the desired region. Save.
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Success!


I tried to suggest the "easiest" option, which was using Views. If however for some reason Views won't allow you to render a full node view - with comments enabled - then you will need to create your block programatically using hook node view. But you still get the idea. The purpose is to take advantage of the existing comment-to-node architecture to avoid writing custom code as much as possible.