I was wrong saying the granules are larger. They are, in fact, smaller but weigh less (see photo).
Picked up Diamond salt a year ago while in Pittsburgh as I've never seen it in my stores. I was interested after Traca mentioned that most restaurants used "the red box."
And because I am the geek that I am, I weighed out the salts since I don't have the S/F/A/H book to view her comparison chart.
Clockwise, starting in upper left: 1 TBL each
Diamond Kosher: 8 grams
Morton Kosher: 16 grams
Sea salt (fine): 22 grams
Morton Iodized table salt: 20 grams
The issue: Say you were following a recipe originally developed with Diamond Kosher salt that called for 1 TBL -- you would get far more saltiness if you simply measured 1 TBL of any other salt variant.
But if the recipe specified weight, you should get the same result.
LONG LIVE RECIPE WEIGHTS!
PS: The Diamond box says 1/4 tsp = 0.7 grams so their TBL would be 8.4 grams. Obviously their equipment is more accurate than my kitchen scale.
https://pix.sfly.com/asfwJ0