If I enter a synonym of the correct answer, or near-synonym, I get a second shot, then if enter a second synonym, I get a multiple choice. This means that some words can completely remain passive vocabulary (word that I understand but never comes to mind when I want to make a sentence) and still get to mastery level 9. This is one of the words that I understand without problem but never think about when asked, and it's still at mastery 8. There are others like that, up to mastery 9, sometimes there are at least 3 words I could answer that wouldn't be counted wrong. I tend to like whatever solution allows to reduce the time needed to study per day (excessive schedule was the reason I gave up studying with Anki), but here I'd rather see the opposite, in order to have a chance to force these words into my active vocab.
Maybe, for words of mastery 5+, asking the question a 3rd time? That would reduce the number of words concerned.
Or just not increase the mastery after 2 answers of near-synonyms? (=block the def>kana mastery of the word until the user finally starts remembering the word with multiple choice. After all, they're near synonyms, but a careful reading of the definition after the first answer should differentiate between the correct and any near-synonym. Typically we enter near synonyms because we only read the first word of the def and rush... Or sometimes we just know it's a wrong answer that won't be counted as wrong.
I could definitely, next beta-round, allow users to choose how many "retries" they get. That would be relatively easy to do.
I have also thought about this - are there other hints we could give to help the user after the 2nd try? Step 1: Question, give synonym Step 2: Question, no hint given --> give different synonym Step 3: Question, give first character (hiragana/katakana)
This new, third step would give them a big hint, but not the full answer.