I suppose we could add an option for that in the finished build, but since they don't make the slightest difference to Pleco's importer they seem like a waste of space - then again, if we were really that space-conscious we'd either compress the files or use shorter tag names, so I guess readability is worth a few dozen extra K.
Firefox works really well for large XML files, so if you try opening it with that you might have better luck - there are also utilities out there that'll insert line breaks into XML for you.