First thing:

The hammer fail in the video you posted had nothing to do with bad technique really. If you throw in flip-flops, you deserve what you get.

Second thing: Throwing in the heavy events isn't something you read about, dash out onto the field, and break world records. There's a learning curve. We call this "Time on the implement."

Third thing: Throwing the heavy events is not easy. If it were, the English would do it.