The throwing hand is an instrument of warfare. A weapon so to speak. Weapons must be cleaned, checked and always kept safe & well protected.
I see what the NECC says. You can ask 10 pitching coaches about pitching styles and you will probably get 10 different answers. Same with hitting techniques.
As a catching instructor myself I subscribe to the theory that says you protect that hand (and arm) at all costs. The only time that hand NEEDS to be in front of the body is when it is helping to block balls, but again it is protected by placing it behind the glove in the 5 hole when blocking balls. I teach that all other times that had is to be free from accidental injury, foul tips, foul balls, etc. The hand doesn't need to be near the glove because in the event the catcher needs to make a quick throw to a base (steal or pick-off) the transfer from glove to throwing hand happens at the ear anyway not out in front of the body.
I'm sure this technique will stir quite a bit of disagreement and that is fine. To each their own.
To the original poster...protect that hand at all costs. Keep it out of the way. There is one position on the field that is not only allowed, but encouraged to catch the ball with one hand...you guessed it. The catcher.
Catching lessons will be available at an indoor facility in Lancaster starting November 2013. Feel free to PM me for more information. The facility isn't open yet so I'm not making full-blown announcements about it. However, it will be open. Nov 2 is the grand opening. We will have 8,000 square feet of training space including an area long enough to practice full throws to 2B.