So, I bought those cool devices for pushups and they actually work. But... I soon experienced pain in my right shoulder (Im lefty). So I googled about that, I saw many people complaining about pain in their left shoulder, what they call the rotator cuff. Since most people are right handed, I deduced that the Perfect Pushup can cause pain on the non-dominant shoulder in some folks. Hence the "some", since most people seem to have no problem with it. So, has anyone here experienced this?