I am only guessing at what might occur, Mary. Down here, and we have completely different growing conditions than you do in Anchorage, we plant our garlic in the fall, and during the fall, winter, and early spring, those single cloves develop into full bulbs. I find that an amazing process. When we plant in the late winter/early spring, those cloves are supposed to simply grow larger, but not divide into full bulbs. That's what my PhD vegetable expert told me a few weeks ago. I don't know this for a fact, but I did this late-planting and will know what happens with those cloves by late summer. It's just another one of my "experiments".
I have never seen rust on any of my garlic leaves, so I don't have a clue why that occurs. It seems to be a problem in the west though, but again, why, I don't know.