With regard to the idea of `perspicuity’ it seems to me that the history of Biblical interpretation rules this idea out of court. The scripture is evidently not clear and what one takes out of it depends strongly upon one’s context and the hermeneutical tradition to which one is heir.
The only way scripture can ever be `clear’ is through the action of the Holy Spirit. It seems to me that any doctrine of scripture that wishes to argue that the scripture is in any way `clear’ must take the Spirit into account. This suggests that any doctrine of scripture is linked in a fundamental way to a doctrine of the Spirit, not just in the initial process of the writing of scripture but in the continual state of these inspired writings existing as scripture.
This raises issues of hermeneutics. Might it be necessary for a doctrine of scripture to take into account not only the documents themselves as scripture but the readings of those documents as, in some sense, scripture also. Can one read scripture as scripture without the Spirit mediating?