When you register, you need to have your decklist filled out.
And then you get deck checked. It is not optional.
Not 100% correct Gorn. Straight from the OP website:
"Day-of Nationals Player Registration Process
1) Though the official registration times are 9:00 a.m.–9:30 a.m., players may get in line in the TCG Event Hall as early as 8:00 a.m. Event staff will begin registration early, if possible. To proceed through registration, your deck list and registration slips must be completed. You may only register yourself, and you must be present to register.
2) Go to the Check-In table. Your registration slip will be taken, and you will be asked if you wish to have your deck checked. If you do, you will be sent to the deck-check area. If not, you will be directed where to drop your deck list. Remember, whether you proceed through deck checks or not, your deck and its contents are your responsibility.
3) After your deck list has been accepted (at either location) you will receive the following:
a. Player Responsibilities information
b. National Championships promo claim ticket
4) Proceed to the next area with your claim ticket, and you will receive your National Championships promo card, pin, and T-shirt.
5) You must review and follow all regulations on the Player Responsibilities information sheet.
6) You’re done! Be back in the tournament area no later than 10:30 a.m. for the player meeting."
Keith