Steven's Advice should read: "Draw a number of cards up to the number of your opponent's Pokémon in play. If you have 7 or more cards (including this one) in your hand, you can't play this card." This errata replaces text of "more than 7" with "7 or more". If a player has 7 cards in his or her hand (including Steven's Advice), they cannot play the card.
Source: PUI Announcement (2004-10-01)