The crew at SicFit posted this video with some feedback from workout 11.4 of the 2011 CrossFit Games Open.
Obviously 2 full rounds isn’t possible! I didn’t even get one….. 🙂
In all seriousness, though… I would love to see video of someone moving as fast as he mentions in the video through all of those reps. That would be INSANE.
11.4 | Is Two Rounds Possible? from SICFIT on Vimeo.
Smashby's Training Blog 
Obviously the jumping over the bar part is what is messing them up. 2 seconds per burpee is impossible when you factor that in.
You could time yourself doing 20 burpees as fast as you can, calculate the time per burpee, then add 20-25% to figure out a solid and somewhat realistic pace.
Here’s the thing, Joe… throughout the first few weeks of the CrossFit Games Open, there have been more than a few “suspect” score/results submitted.
That has lead to a pretty strong sense of disbelief among many CrossFitters.
Physically, many people think that 2 rounds in this workout is approaching the limits of human capacity! However, if someone out there CAN do it… we just want to see it and be in awe!