Make diff comparison page themable

I want to disable/theme printed current revision of node below Diff comparison table. Currently it's hardcoded in the end of diff_diffs_show():

While it would be probably possible to break in via hook_nodeapi() it seems to me wrong, like correcting one bad behavior using another bad behavior. How about inserting checkbox to enable/disable output, or even better, output whole diff page using theme function so it's overridable ?

I can explain use case for this: currently I am making Panels integration for Revisioning module, and it will be possible to output revision using Panel Page. Next step would be to display node below Diff table using Panels too, or atleast to hide it completely, cause I need to have consistent theming both in "view revision" page and Diff page. I don't want to make template just for that Diff page.

Also, next step would be possible if Diff was fixed: It would be possible to implement "Compare two revisions" CTools content type that would take 2 arguments (2 "contexts") and output diff compare table in Panel Pane. But currently output of diff_diffs_show() is too big and not convenient for using in Panel Pane.