I agree with the importance of magnesium. Very easy to read article. However, I think I was actually overdoing it or more importantly not balancing the ratio of calcium to magnesium. I was taking about a 1,000mg of magnesium daily in supplements and maybe a little more in food and about 1200 mg of dietary calcium daily (I sat down and calculated mag and calcium from foods I normally eat). I then found this interesting article. I am hypothyroid. I have since cut down on the amount of mag to 200-400 mg and feel better energy and increased absorption of iodine(loose stools I was having should have been a indicator to back off of the mag). So, I'm not suggesting it isn't important (especially as most people's diets are calcium dominant) just important to make sure calcium and magnesium are in appropriate ratios to one another.
In summary, to balance calcium and magnesium keep these points in mind: a normal person need a cal/mag ratio of about 2:1; a hyper needs more magnesium and a hypo needs more calcium, but these ratios need to be constantly adjusted as you approach normality; irregular heart rate can be a sign of either too little calcium or too little magnesium; the key to knowing whether you need calcium or magnesium is the strength of the heart beat, not the speed or the irregularity--if it's too strong, take more magnesium and if it's too weak, take more calcium.