Overrun, a standard action?

[Grayhawk]

PHB p.157:

'You can attempt an overrun as a standard action taken during your move, or as part of a charge. (In general, you cannot take a standard action during a move; this is an exception.) ... You can make only one overrun attempt per round.'

Why is overrun labeled as a standard action? As I understand it, you still get to make a standard action before or after your move, or an attack at the end of your charge (otherwise it wouldn't be a charge, right?).

What difference would it make if I renamed it to a free action, keeping the 'You can make only one overrun attempt per round' text?

 

[shilsen]

Presumably it is a standard action so that in a round where you overrun someone you can take no other action. Since overrun is a standard action and it occurs during your move, that's it for the round as far as available actions are concerned. Making it a free action would allow one to move (making an overrun during it) and take a standard action either before or after the move.

BTW, you can't overrun as part of a charge. That was errataed out.