[BeetleB]

Because they strongly disagree.

If I have soda cravings, I can take a single Tic Tac. It doesn't satisfy my soda cravings, but crucially, it prevents the soda itself from satisfying those same cravings if I do subsequently drink it.

Usually I crave soda after a high salt/fried food. Giving myself a tiny amount of sugar (Tic Tac has 0.5g) removes the salt/fried taste, and I just can't get the good soda effect I know I would have gotten without the Tic Tac. There just isn't a point for me to take soda after a Tic Tac.

So yes, substituting a small amount of sugar for a large one can be very effective.