The issue here is you are conflating doctrine and truth. Doctrine is not truth. That it's not possible. The Spirit doesn't guide people to doctrine. Doctrine can reflect truth, but it can't BE truth. Jesus is truth. So being guided into truth is to be guided to Jesus. Truth then, is manifest in our character, our actions, how we live, how we treat others, in following Jesus's example.
It is impossible for man to completely know or understand God, otherwise we would BE God. By definition doctrine is about teaching. Therefore it is impossible to have complete teaching (doctrine) about God. It will always be flawed. 2 Tim 16 says that scripture is profitable for doctrine, meaning scripture is beneficial for teaching. If scripture has the ability to "improve" doctrine, that implies there is room for doctrine to improve, therefore it is not truth.
When any Christian interprets scripture we are doing our best to understand God in some way, but again, no one can completely understand God, that's not possible. We may understand in part. We may understand a layer or two or even ten, but we cannot understand God in His entirety. Which means we cannot have complete doctrine/understanding/interpretation... ie we are all wrong/incomplete to some degree.
Truth on the other hand, produces character, fruit, freedom, healing and salvation... THAT is what the Spirit is guiding us all to all the time. Where we all fail to some degree is in our ability to describe this truth to ourselves & others (doctrine) because we are incapable of understanding completely. However, as we grow in truth, we grow in understanding of Jesus's nature & character (because that is with truth guides us to) and when we grow in understanding Jesus's nature & character we are better equipped to understand scripture and thus develop more sound doctrine... In other word's one's doctrine will only be as mature as one's fruit. If someone claims to have great doctrinal understanding, or "proper" interpretation of scripture yet has bad fruit (questionable character), or no fruit, in their life... why should anyone listen to them? No matter how good their argument may sound? We know the true from the false by the fruit, not the doctrine.