In Swedish, much like in English, coordination over gaps conserves syntactical role.
The relative pronoun* 'som', for some speakers at least, seems to permit coordination where the explicitly stated pronoun is a subject and the gap is an object, thus violating the conservation of role. A similar weird sentence in English would be, _ marking the coordinated gap.
?the guest that arrived and you received _.
* There is some controversy regarding whether it even is a pronoun and has any role in the VP or is just a complementizer, but I hold that the existence of mistakes such as the genitive 'soms' (should be 'vars') argues in favour of it being a pronoun.