haha, you sound like a tadoku reader
I never obeyed that rule, but I always try to get the meaning with context first, guess and afterwards look-up to see if my guess was correct.
Depending on which level of japanese one is at, it does or doesnât make sense to add everything you read to your reviews. But I think if you are still within your first 4000 words or something itâs more worthwhile to use premade decks with common words.
But occasionally making a deck with themed vocabs (like a pregnancy related deck) to better be able to follow a themed book can be a fun and useful change of things. In such a case I would skim the book first to gather useful vocab (thereâs probably a tool for that), then make the deck (not many vocab, but useful ones, 100 max), then learn the deck for a week or two and then read the book again.