Copy from deck to inventory feature

Current wishlist includes several similar features. The main idea is to be able to copy/import cards from deck to inventory. Why do you want it? (And do not ask for adding set information to the decks. I won't allow creation of all-lands-with-different-pictures nonsense.)
You want to quickly add precons? Help me converting them to .mai format. It is the proper way.
You have some decks in other formats and want them to merge with the inventory? Spend some time: convert them manually and use inventories (not decks) from now on (you can merge inventories if needed).
Why do you need it? Explain it. Convince me. Personally I do not think this feature is needed.
You want to quickly add precons? Help me converting them to .mai format. It is the proper way.
You have some decks in other formats and want them to merge with the inventory? Spend some time: convert them manually and use inventories (not decks) from now on (you can merge inventories if needed).
Why do you need it? Explain it. Convince me. Personally I do not think this feature is needed.