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In 2002, Cooks Illustrated published an excellent guide on the different beef roasts. You can access it here: http://www.cooksillustrated.com/images/document/howto/ND02_BeefRoasts.pdf
Don't worry when you open up the PDF document. Yes, there are some technical errors on it and some of the data is cut off.
The top sirloin is a cut with excellent flavor at an affordable price. It's described as "This cut has big beefy flavor. Aside from the vein of gristle that runs through it, which we found slightly unpleasant to eat, the roast was tender and juicy."
Yes, it is a roast. Yes, you can put it in the crock pot. You want to do it low and slow. It will take longer but you've got that gristle in there ..... the low and slow will help ensure a tender finished product.
Also, note, if your gathering is not going to be big enough for the 14 pounds, you can cut the roast in half now. Cook one half as you normally would and put the other half in the freezer to use at a later date.
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