The effect of placing this code here is that for each portlet rendered on the page, you have an HTML comment placed below it that displays how many milliseconds it took to render that portlet.

It then outputs all the comments as HTML code, exactly as was done on the original page but with the exception that this time, it displays the additional comment that the user provided.

Indicates a comment that is not displayed. Prevents any enclosed text or HTML source code from being parsed and displayed in the browser window.