title: Why does Google's AMP Project (Accelerated Mobile Pages) ban form and input tags?
body: <p>According to the
  <a href="https://github.com/ampproject/amphtml/blob/master/spec/amp-html-format.md" rel="noreferrer">specs</a>
  the AMP project bans HTML tags like form, input, textarea, select and option.</p>
  
  <p>However, <a href="https://www.google.de/webhp?esrch=AcceleratedMobilePages::Preview,AcceleratedMobilePagesDesktop::Promo&amp;gws_rd=cr&amp;ei=1HwXVq2YHcWdsgGvkbY4" rel="noreferrer">Google's AMP Search Page</a> uses a form and input tag.</p>
  
  <p>What's the reason for banning input elements?</p>