Just to point out that hovering over the link shows URL-encoded codepoints, i.e. %u200B (in Firefox, for me, at least). I do think it's a better solution than the existing approach with GET parameters which does look clumsy.
Here neither. But even then, for very long URLs (can easily happen with that SEO crap), just hide your tracking byte so that when Chrome/FF truncates the URL for display, the bytes will be inside the hidden area.
