One of the clearest influences of Protestant thinking in northern Catholics is their exaggerated attention for the Scriptures. I think it depends from the fact that even when they are cradle Catholics, they grew up in an environment where Protestant relatives and neighbours threw verses at them like grenades, and they must have thought the weapon is a fearful one indeed.
Well, it isn't.
Proddies have been throwing such grenades at each other with remarkable zeal for several centuries now, and I do not think there have been many who thought the hand-picked verses of their opponents were better than those hand-picked by themselves. The procedure is also questionable in itself, then either the quotation is rather long or very often the context is lost, and as no one – not even a bible-verse-shooting Protestant – can put every Biblical quotation in its entire context by heart, the argument loses much in efficacy. The more so, when the citation becomes so short as to be thrown around at one's convenience, like the “do not judge” curiously so well mastered by those clearly worthy of the harshest judgment.
Scriptural quotations do not work, because the Bible does not have the Truth. The Church has.
Put in a different way, first I believe what the Church says, and then I believe where I find it in the Bible. As a result, no quote from the Bible can be taken authoritatively, unless it is clear that the quote is meant and interpreted in accordance to what the Church teaches; but if this is the case, then it is much better to make the point arguing from what the Church believes, than from what the Bible says.
This endless Bible-quoting also plays in the hands of the Proddies, because it reinforces them in their erroneous opinion that the Bible, not the Church, has the Truth. As a result, they will react to every barrage of biblical verses with another barrage of biblical verses, and the discussion will end absolutely nowhere as, again, abundantly demonstrated by the astonishing proliferation of Protestant sects.
On the contrary, every Protestant should be confronted with a paradigm shift (whether he accepts it is another cup of tea, of course) and be told in no uncertain term the Scriptures can only be the reflection of a Truth existing before them and outside of them. Therefore, the reflection is only correct insofar as it correctly transmits the Truth reflected, failing which the reflection will be in nothing more authentic than the one provided by those deforming mirrors you look at if you want to have a laugh.
I hear, here and there, that Catholics should have a better knowledge of Scriptures. Maybe so; but given the abysmal ignorance of our times, the risk of getting the meaning wrong or even tragically wrong (“do not judge” is my absolute favourite), and the sheer complexity of Catholic teaching I suggest the effort should be directed towards a better knowledge of the teaching itself. If you ask me, for most people and in most circumstances the rediscovery of old Catechisms and the reading of books of Catholic apologetics or theology is far more fruitful than hours spent in reading the Scriptures without adequate instruments for their proper understanding.
Granted, it will sound less impressive than having one or two dozen citations learned by heart and ready for use; but one will know he is right.