How is that easier than downloading than downloading the ascm file, which causes ADE to automatically download the book into it's library, then one single drag'n'drop puts the book on your reader?
You beat me too it! Just to add, when you are asked to download the ascm file, just click on 'Run', not 'Save' and Adobe Digital Editions will automatically open up and download the book.
Afterwards, you may wish to use Calibre to manage your books. You can find the book in My Documents > My Digital Editions. Just drop the file on to the Calibre main window and you're done!