In a small bowl, combine the onion powder, garlic powder, pepper, and salt, and rub them onto the roast, coating it as much as you can.
Place the roast in a 5 quart crock pot, and add the beef consommé, French onion soup, 3/4 of a soup can's worth of water, and the Worcestershire sauce into the crock pot.
Cover and cook on LOW for 6 hours.
When the roast has cooked through, remove the roast, slice it thin, and return the slices to the juice in the crock pot to absorb moisture and more flavor.
Meanwhile, slice the hoagie rolls lengthwise, toast them, and butter the inside. Add cheese, if desired.
Remove meat slices (I find kitchen tongs to be helpful for this) from the crock pot, and pile meat onto the hoagie rolls.
With a ladle, get some juice from the crock pot and put it into a small bowl, to serve with the sandwiches (au jus - to dip the sandwich into).
Helpful hint: To thicken the au jus, pour it into a saucepan on the stove, and bring to a boil. Mix 3 tablespoons of cornstarch with 1/2 cup of cold water in a separate cup (make sure it is mixed completely), and gradually pour the mixture into boiling au jus. You probably won't need it all, and the longer it boils the thicker it will become too.