oa De zin die wij merken dat ook voor linguïstische problemen zorgt

A recent social media upheaval on the grammaticality of a certain sentence from a popular song written on the occasion of the inauguration of the new Dutch king turns into an interesting linguistic discussion. The sentence appears to involve the extraction of a relative subject pronoun from a seemingly factive sentential complement, and in line with facts from other languages (a.o. whom in English), the relative subject pronoun seems to be interpreted by native speakers as an object, which is a problem for current syntactic theories.