Cut beef into 5 pieces. Put several garlic into each piece making a hole in the meat with a knife and inserting the garlic cloves. Put beef into an industrial size baking pan. Pour BBQ sauce, worcestershire sauce, and salt. Pour 1 1/2 cups of water into bottom of the pan. Roast at 375 degrees for 2 hours. Remove pan from oven and turn the meat over. Pour another 1 1/2 cups of water into the bottom of the pan. Return to oven for another 1 1/2 hours. Remove meat. Allow to cool. Refrigerate beef. Pour the broth from the pan into quart jars. The next day... Slice meat. To make gravy... Remove fat that has accumulated on top of broth. Melt it and combine it with an equal amount of flour to make a roux. Add rest of the broth to the roux to make gravy. Warm sliced roast beef in pot with gravy. Serve roast beef on a sub. Add some gravy and dress with mayo, lettuce, tomato, and pickle. Sometimes the best Po'Boy is a sloppy one - the more napkins the better!