I am using a dropdown menu that I have used many times in the past on a new site and it is stalling in Chrome and animating with choppiness. I have looked at the code for countless hours trying to sort out why it fails to animate fully and have not been able to figure it out.

Here is the website.
Here is a website that I have used it on that works perfectly.
Here are the original reference files.

Your help is greatly appreciated. Thank you in advance.

There were intermingled Javascript comments and HTML comments. ie. //<!-- and //-->

This was weeded out and it seemed to work for a bit, then went back to being jerky. Strange!