Yes that test site is okay.
The weird thing is my staging site isn’t and it doesn’t seem to be cache, CSS or plugin related.
I’ll have to play around with things a bit more but there does seem to be something weird going on with this site. Between 768 and 1024px the white space below the widgets is increasing as shown in some of the previous screencasts.
I will keep trying to nut this out. I know it should work like the test site but its not.
I will see if i can work out why. It may take some time though.