Very true, MaxWilson.
To clarify: The point of the meat-grinder is not just strong defense. That's good, but it won't win the game. The point is to keep your opponent distracted and wasting resources while you are making progress elsewhere. He throws all of his troops into the meat-grinder. You capture provinces, search for sites, and generally build your empire.
Then you return and crush him when you have an overwhelming advantage.
Needless to say, this strategy works exceptionally well if you can combine it with some other strategy (or strategies) to strangle your opponent. For example, heavy use of spies, blasting his provinces with hostile magic, raiding parties behind the front lines, etcetera....