It absolutely does help!
I also wasn't aware that a heavy light cycle could cause a calcium deficiency but it absolutely makes sense why it would.
What's funny is that I was talking to a buddy of mine just the other day about CalMag and when he was using it. Then the next day, I notice what looks to be what we were talking about the day before. I've got calmag on order and it should arrive tomorrow. I plan to add a dose to my nute mix this next watering cycle, which will probably be in another two days.