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I think its pretty helpful though.

There were also some Anki decks with Japanese only definitions, eg. Tanuki.
There is a new one for lower intermediate learners, Joseph's deck (I haven't used this one).
The author of The One Deck also tried to create a monolingual deck with the n+1 method.

I prefer pre-made decks, Japanese definitions are already given. The card has already example sentence and a L2 definition, and if I don't understand something in the L2 definition, only then I create new cards, I learn those cards today, and tomorrow I can learn the card with its (now understood) L2 definition in the pre-made deck.

There has never been a better time to get rid of bilingual dictionaries, because I can learn every frequently used word with the least effort.

This seems like a great method for people who like reading dictionaries and making flashcards