Yes, absolutely PDF is better, even without someone's malicious intent. Many corporate HR depts use Microsoft Outlook email. Try attaching the resume as both a

Yes, absolutely PDF is better, even without someone's malicious intent. Many corporate HR depts use Microsoft Outlook email. Try attaching the resume as both a Word doc and a PDF doc to an Outlook email. Then open by double-clicking in the email message like a typical user. The Word version goes into a double-paned "reading mode" while the PDF will appear as you intended.