Originally Posted by taosaur
If I knew C++ or Java or whatever Calibre is built on, I could rewrite the whole thing.
Having to write chunks of the program yourself (I include the pseudo-script needed to tweak imports and conversions in that characterization) for tasks that could be accomplished with some check boxes or drop-downs is one of those things that makes Calibre baffling/painful to start using.
Alternatively, being able to customize things like the reader's CSS without having to mess about with limited dropdowns and checkboxes is one of those things that makes calibre completely awesome and a joy to use.
Edit: Maybe I'm just weird, but this exact reason is why I prefer ebook readers like Stanza (RIP) and Freda over Kindle and iBooks, because the former let me set my own colors based on RGB values and tweak pretty much every layout option imaginable and the latter let me pick anything I like as long as it's black-on-white, brown-on-sepia, or gray-on-black.