Fungo the CB my son threw at 10-14 breaks 25-30' out front and was a long sweeping curve. The Ther was no "tommahawk" motion and it was not stressfull on his elbow as the arm motion was smooth . He was taught by Jim Ridley former Blue Jay now Twins pitching scout how to throw a ML CB witch has a tight rotation and breaks 3-4' in front of the plate. It has a violent break as opposed to a gentler break. At the younger age the batters knew it was breaking but had trouble hitting it. At an older age the more experienced batters had a better chance of making contact.
I was assured that the CB he threw at the early age had no more stress than a FB. There was no abrupt snap that trabsfered stress to the elbow. I watched him very closely all his practices and games and questioned him to the point of annoyance about his arm. My son is as close to perinoid about his arm health as any pitcher and has pulled himself twice over the last 2 years because his arm was stiff in the elbow area. The 1st time was in freezing weather that had intemitten rain ,sun and everything in between. He had 7 Ks in the 1st 3 innings and did not want to risk injury. He started a game in Cleveland a week later and pulled himself because he was still stif. Went to the doctor who said he had a stressed Ulnar and to keep throwing until the swelling went down. It was more a mental thing than a serious injury and he was fine once he knew what it was.