Ask yourself this question: Would you rather receive a game loss in round one or in round ten?
Once upon a time, almost two years ago, judges would count all of the decklists during round one of a tournament. It was an impressive sight to behold. Dozens of judges would sit in the judge area and silently pour over the hundreds of decklists turned in during the players meeting looking for deck registration errors. It would often be the case that around 5% of the decklists had some kind of clerical error, such as too many of a card, too few cards in the maindeck, or the wrong number of cards in the sideboard.
The History of Deck/Decklist Problem
Deck/Decklist Problem is the name given to the infraction committed if a player has an illegal deck, decklist, and/or sideboard. It is often referred to as DDLP. Back in 2005, if a player committed a DDLP at day two of a Grand Prix or at the Pro Tour, then they were ejected from the event. At what is called 'competitive' level events now, the penalty was a match loss. At that time, players were expected to have a high level of rules knowledge, and they were expected to be able to fill out a decklist without error. For this reason, the penalty for DDLP was very stiff.
Over time, events grew in attendance, and the playerbase began consisting of more new-comers to the game. The Judge Program began to realize that these strict policies caused it to be harder for new players to enter competitive level environments. DDLP was downgraded to a game loss at Competitive and Professional REL.
Other changes were made to DDLP as well. Originally, a player's decklist was gospel. What you wrote on the decklist were considered the cards that you intended on playing whether you actually intended on playing those card or not. This led to incidents such as the Trinket Mage/Treasure Mage incidents where a player would accidentally write one of these on their decklists when they meant to write the other. When judges went to fix the deck, they would require the player to play the card that they wrote on the decklist, which was very obviously not the card they intended on playing. This was changed so that when there is a problem with a decklist, then the decklist is altered to match what the player is playing. This solution is more reasonable in most situations.
The Elimination of the Count
Other changes in philosophy shifted the way that judges verify decklists. Magic tournaments became so large that traditional means of counting decklists became impractical. Judges were spending dozens of man-hours collecting, counting, and verifying decklists at the start of the day in spite of covering the floor for judge calls. As a result, the Judge Program began eliminating the process of counting all of the decklists. If you go to a Grand Prix or a Pro Tour, it is possible that a judge will never look at your decklist except to verify your name.
Decklist Errors are Happening More Often
Now, you may say that this means that it is easier to get away with errors on your decklist. You would be correct. Players are a lot less likely to receive game loss penalties for DDLP. DDLPs aren't being penalized as often as before. Since players aren't receiving these penalties as much as they were, players are not being reminded as often of the importance of filling out their decklist correctly. Finally, I get to the crux of the issue. Over time, as the knowledge of DDLPs and their importance wanes, the prevalence of DDLPs will increase. If a player is sloppy filling out their decklist, they are more likely to continue to be sloppy since they are less likely to be penalized for problems with their list. Also, this effect won't be seen since a lot of the lists aren't looked at for errors.
Decklist Errors are More Important Than Ever
However, it is important for players to keep this point in mind: Decklist errors now result in a penalty that can come at any time in the tournament. I asked earlier whether you would rather receive a penalty in round one or round ten. I would guess that a majority of players would rather get their game loss in round one. In round ten, you are likely playing a player with a higher skill level than the opponent in round one. That means that it is more difficult to win two games in a row in round ten against a statistically more difficult opponent.
Also, since deck checks are random, you may randomly receive a game loss penalty for a DDLP in the last round of the tournament right before top 8. This is a massive departure from earlier when judges would find most DDLPs in round one. In addition, all top 8 decks and lists are checked prior to the top 8. If you have a problem with your list that is caught in top 8, you will receive a game loss in top 8.
All of this means that it is much harder now to win a tournament with a decklist problem than it was two years ago.
Take the Time
I hope you enjoyed our brief foray into the philosophy of DDLPs. Remember, only you can prevent game losses for Deck/Decklist Problems. Please take the time to fill out your decklist correctly. Head Judges typically give an extra minute for players to go over their decklists and count the cards in their deck and sideboards. Use this extra time to prevent a needless game loss penalty.