Can checked swing be a 'fourth out' appeal?

[johnnyg08]

I realize that Coach JM...i think we all know that if the PU calls swing that's strike three and play at 2nd doesn't matter unless strike three is in the dirt at the point in which the B offered at the pitch...at that point the PU must act quickly and let the catcher and B know what's going on ASAP...the no catch mechanic should come into play here (if the ball is in the dirt) but TussAgee is right...this could get really sticky...when in doubt on a sitch like this...it makes most sense to call strike 3 on the check swing so that would eliminate the appeal in most instances as your BU wouldn't take a strike away from you as the PU...