You'd think after going through so many bags like the one in the video above that I'd have figured out how to open that chained string knot securing the top of it.  Well, impatience will no longer lead me to grabbing those scissors and hastily cutting the top clean off.  Because I found the solution to opening a sac of rice.

 

Basically, you cut the nearest loop to the edge of bag on the 'chained' string side. Then you grab the chain of string and it should pull freely right across that side and then continuing on the other side until all the string has been pulled out completely.  This was not my solution.  Thanks goes to:

Beehexs at YouTube