The "effect" entry has more details on exceptions, but the following applies here: "If an action plays a card from your hand (or discard pile) as part of its effect, then that card must be in your hand (or discard pile) before you can begin to perform that action."
I think GE's example falls under the "playing a card" rules instead, where
Dark Approach is being played, but is discarded only after its effects are performed. Like he said though, Toldea can't grab the
Dark Approach used to play him with his own effect.