Actually, yes there is.
We just unveiled an upgrade to the website that contains a video player with variable speeds. However, it doesn't work in every browser, so if you don't see it, you may need to try another browser. I know for a fact that it does work in Google Chrome.
If your browser supports the feature, you will see a small "1x" in the lower right-hand corner of the video player, just to the left of the full screen icon. When you click on that, it will pop up a list of speeds for you to choose from, including 0.25x (quarter speed), 0.5x (half speed), 0.75x (three quarter speed) and 1x (full speed).
Regards,
Jonathan Atkinson
Ballroomdancers.com