Can you hide the controls of a YouTube embed without enabling autoplay?

Set autoplay=0

<iframe width="100%" height="100%" src="//www.youtube.com/embed/qUJYqhKZrwA?autoplay=0&showinfo=0&controls=0" frameborder="0" allowfullscreen>

As seen here: Autoplay=0 Test

To continue using the iframe YouTube, you should only have to change ?autoplay=1 to ?autoplay=0.

Another way to accomplish this would be by using the YouTube JavaScript Player API. (https://developers.google.com/youtube/js_api_reference)

Edit: the YouTube JavaScript Player API is no longer supported.

<div id="howToVideo"></div>

<script type="application/javascript">

    var ga = document.createElement('script');
    ga.type = 'text/javascript';
    ga.async = false;
    ga.src = 'http://www.youtube.com/player_api';
    var s = document.getElementsByTagName('script')[0];
    s.parentNode.insertBefore(ga, s);

    var done = false;
    var player;

    function onYouTubePlayerAPIReady() {
        player = new YT.Player('howToVideo', {
            height: '390',
            width: '640',
            videoId: 'qUJYqhKZrwA',
        playerVars: {
            controls: 0,
            disablekb: 1
        },
          events: {
            'onReady': onPlayerReady,
            'onStateChange': onPlayerStateChange
          }
        });
    }
    function onPlayerReady(evt) {
        console.log('onPlayerReady', evt);
    }
    function onPlayerStateChange(evt) {
        console.log('onPlayerStateChange', evt);
        if (evt.data == YT.PlayerState.PLAYING && !done) {
            setTimeout(stopVideo, 6000);
            done = true;
        }
    }

    function stopVideo() {
        console.log('stopVideo');
        player.stopVideo();
    }

</script>

Here is a jsfiddle for the example: http://jsfiddle.net/fgkrj/

Note that player controls are disabled in the "playerVars" part of the player. The one sacrifice you make is that users are still able to pause the video by clicking on it. I would suggest writing a simple javascript function that subscribes to a stop event and calls player.playVideo().