"WRI JS method" refers to the embedding code provided by the CDF export wizard in Mathematica, which includes a call to the JavaScript hosted on our website and also parameter settings expressed as JavaScript. For example:
<script type="text/javascript" src="http://www.wolfram.com/cdf-player/plugin/v2.1/cdfplugin.js"></script>
<script type="text/javascript">
var cdf = new cdfplugin();
cdf.setDefaultContent('<a href="http://www.wolfram.com/cdf-player/"><img src="SimpleParamTest.png"></a>');
cdf.embed('SimpleParamTest.cdf', 600, 500, {color:"Red", size:100});
</script>