Yes, I read the underlying paper a while back. It only looks at the very first step of a Dow-like process, before any electrochemistry happens. Instead of dumping hydroxide in a tank, they expose it to hydroxide in a serpentine flow path. When I was reading into this before calcium didn't seem to be too big of a problem for the Dow process because the calcium compounds are more soluble than magnesium hydroxide. They were actually adding more calcium with the lime. So their comparison may be to a different method than the Dow Process. It didn't seem particularly useful.
Then you neutralize the magnesium hydroxide with hydrochloric acid to make Magnesium chloride and do molten salt electrolysis on it to make pure magnesium and chlorine.
Then you neutralize the magnesium hydroxide with hydrochloric acid to make Magnesium chloride and do molten salt electrolysis on it to make pure magnesium and chlorine.