The process of muscle movement involves an exchange between calcium, the contactor, and magnesium, the relaxant. If I want to move my hand towards my face the muscles in the upper arm that need to pull the lower arm up influx with calcium causing them to contract, while the opposing muscles influx with magnesium, causing them to relax. If I want to extend the arm back out the muscles that just contracted by the influx of calcium now influx with magnesium causing them to relax, and the opposing muscles that were relaxed by the influx of magnesium now contract by the influx of calcium, which allows the arm to be pulled back the other way. This is very basic anatomy and physiology and has been well known for a long time by everyone with even basic training in medicine. Now that we all are aware of this basic principle, let's get back to rigormortis. When a person dies there is an influx of calcium in to the muscles causing them to contract tightly (rigor). Because magnesium can no longer enter the muscles to displace the muscle contracting calcium, the muscles stay in this contracted state (rigormortis) for several days until enzymes finally start breaking down the muscle tissue.
Here is a link explaining the process of muscle contraction by calcium. It also touches on the process of rigormortis.
If all this evidence I have posted cannot get the naysayers to understand their error then I guess they can go ahead and screw themselves up. Even the fact that Moreless was recommending all that extra magnesium from magnesium sulfate and magnesium oxide for muscle cramps shows that Moreless knows that I am right. If he really thought that calcium relaxed muscles then why didn't he recommend his calcium drink? It will alkalinize the body just as well as magnesium. So the only answer is that he knows calcium causes muscle contractions, but he is not admitting to his error.