Imagine all the fake accounts, beginning to trade all the cards with one-another. The entire concept of having to farm and grind would lose its meaning.
I for one always have an "Elements.txt" file on my desktop, that is always open when I play EtG. It's easy to copy and paste deck codes in to and out of it, + you can make captions and notes on how to improve them, or what you want to play against with them.
If you make an Excel sheet, or any other table based database, you could also keep track of your decks' win / lose rate, potential future upgrade cost, total worth, etc. It's a good way to organize your decks, once you have a plethora of cards, you don't know what to do with.
Peace to you!