<the students choose what vocabulary they don't know at the start of term>
I think students are happier if they can choose their own vocabulary. I don't know any other methodologies that use this. I think Mert is objecting to the dictionary translation that students embark on to find their L1 words in the
target language. During the dictionary part of the translation, the facilitator (for the vocabulary unit the teacher is just a facilitator), just tries to weed out the words in English that are not what students want, in the form of choosing a word in English from multiple entries, that best approximates the intended meaning in Mandarin.
Have you ever tried looking up words in Mandarin in a dictionary (no pinyin please). Challenging, and rewarding at some point.
It's actually a fun exercise for college students. It's more suited to Primary and
Secondary grades however.
The other units of study - pronunciation, grammar, and conversation - are based on the class-generated lexicon.