Blind taste testing in 9/2002 Cook's Illustrated says that most tasters
can't tell the difference between expensive gourmet salts and table
salt--especially in baking. Furthermore, yes, smaller crystals dissolve
more easily and so are better for cooking and baking.
The only consistent exception was a benefit in using larger crystal forms
for seasoning steaks, etc. since the shape was fun on the tongue and
provides a little burst of saltiness. But if you're going to dissolve the
salt, such as in baking, use the cheap stuff.
Allen Cohn
allen@cohnzone.com