If I am slowed (as per the slow spell), I can ready a charge, since I am restricted to a standard action, but if I am not slowed, then I can not ready a charge, since I am not restricted to a standard action per round. What an odd benefit from being slowed. Is this correct?
Unfortunately a charge is still a full-round action, so it can't be readied. The Charge (special attack) has a stipulation that allows a charge with a single move speed if the character is restricted to only a standard action in a round.
Yes, thank you Hyper. The quote you have there says "AS a standard action" this doesn't change the charge special attack from a full-round action to a standard action as far as readied actions go.
Here's the relevant text below and it looks like you can make a charge-as-a-standard-action only during your turn.
PHB p.155, Charge "If you are able to take only a standard action or a move action on your turn, you can still charge, but you are only allowed to move up to your speed (instead of double you speed)."
No, you can only make a charge-as-standard action if you are restricted to a single action during your turn.
The standard action charge is not limited to during your turn; the standard action chanrge is only dependent on whether or not you are restricted during your turn.
While I am slowed, I am restricted during my turn; therefore I am capable of charging as a standard action and can ready a restricted charge, even though the charge itself will happen outside of my turn.