Foreign-language placement tests can sometimes be too long. Do you think it would be possible to place students at a CEFR level depending solely on the assessment of productive language skills?
Receptive skills alone are not sufficient to decide on the proficiency level of a student. Productive skills - speaking and writing are harder to develop and master, so they should be tested, too. Placement tests are normally focused on grammar and although students might be good at it, this doesn’t show anything about their speaking or writing. This is what I think.