Place the roast in a large slow cooker; pierce it all over with a small, sharp knife. Stir the Worcestershire sauce into the water and pour over the top of the roast. In a small bowl, combine the thyme, salt, and pepper; evenly sprinkle over the roast and rub in. Scatter the minced garlic over the top of the roast and press into the surface. Cover the slow cooker and cook on low for 8 to 10 hours, until the roast is tender.
An hour before serving, prepare the sauce. In a medium pot, whisk together the honey, balsamic, water, soy sauce, and cornstarch until the cornstarch has dissolved. Bring to a low simmer and cook, occasionally stirring, for a few minutes or until the mixture has thickened (it will continue to thicken as it cools). Remove from the heat and set aside.
Once the roast is done, remove it to a cutting board. Drain the liquids from the slow cooker and wipe out any remaining fat with paper towels (taking care not to burn yourself). Shred the beef and discard any fat. Return the shredded beef to the slow cooker, stir in your desired amount of sauce, and serve immediately (or reheat on low until just heated through). Serve on sandwich rolls with additional sauce, if desired.
Feel free to top your Slow Cooker Honey Balsamic Shredded Beef Sandwiches with cheese (melted provolone, crumbled blue cheese, get creative!), fresh lettuce leaves, or a simple slaw. The beef is also delicious on tacos or served like a pot roast on a bed of mashed potatoes!