WT publications hold more importance than the Bible in the minds of JW's.
They will never admit this, even to themselves, but if a scripture says "do this" and a WT says "don't do this", the JW's will not do it.
For an example see partaking of the bread and wine.
To answer your question, a JW is taught that they cannot understand the Bible without the help of the WT publications.
Even if a difference becomes clear to a JW they will still side with the WT instruction instead of the Bible, and this is because of the fear they have of doing something 'outside' the scope of the WT instructions. There is a world of hurt ready for any JW who questions a WT teaching.
Splash.
PS. Are we avatar brothers?