Theological Presuppositions and Authorship Issues

In discussing issues of the authorship of the New Testament writings, I often hear the claim that if one accepts a high view of Scripture, one should never entertain thoughts of pseudonymity (the view that someone other than the named "author" has written the particular writing in question).  The converse of this, is that only "liberals" embrace ideas of pseudonymous writings in the New Testament canon. 

And yet I wish to suggest that it is not as simple as, holding to view "A" of Scripture, that therefore one automatically holds to view "Z" of authorship. I know quite a few scholars who have a very high view of Scripture and it's authority, and yet for evidential reasons cannot accept that Paul wrote certain letters within the canon. Howard Marshall is perhaps the best example of someone who holds to a high view of Scripture, and yet does not think Paul wrote the Pastoral Epistles.  Equally, I know of so-called "liberal" scholars who do not have a high view of Scripture and yet hold to the view that some of the disputed writings were in fact written by the named author. 

One cannot come to a conclusion on the issue of authorship, based on a theological presupposition.  That is an invalid move.  How can a theological conclusion change a historical event/process? 

The reason the writings of the New Testament are considered authoritative is because they are understood to be inspired by the Spirit. It is on the basis of their divine inspiration that they are authoritative, and not on the basis of the specific human author that was an inspired instrument (although, historically speaking, it seems likely that many of the writings were chosen because of who authored them [could Hebrews be the exception?]). While these specific writings are inspired they are also human products, in that human processes--including language, style, rhetoric, etc., are part and parcel of these writings. Pseudepigraphy could also be a part of that historical process that gave birth to the writings known as the New Testament.   As Paul Trebilco notes,

We should note that pseudonymous writing was not considered improper in the ancient world, and was common in Judaism.  If the Pastorals are by someone other than Paul the author, who stands in the Pauline tradition and has been considerably influenced by Paul, would be applying the Pauline tradition to new problems in some Pauline churches in his own day, and would be expressing what he believed Paul would have said.  However, because he saw himself as faithful to Paul's understanding, he wrote in his name.  Scholars argue that this was in no way to attempt to deceive; rather it was a way of acknowledging his indebtedness to Paul's theology. 

[Paul Trebilco, and Simon Rae, 1 Timothy. Asia Bible Commentary Series. (Singapore: Asia Theological Association, 2006), 3.]

Conclusions concerning the authorship of a particular writing should be judged on the external and internal evidence of each specific writing, and not assumed due to a theological presupposition.