It would indeed be boring here if we didn't have a steady supply of (out-of-context) textproofing.
Of course, here +John also says that he wrote this because of the people who wish to deceive the believers, so he is giving them advice not to believe the deceivers. This puts a somewhat different spin on things. The New Testament is otherwise full of refrences for the believers to hold on to the teachings and traditions of the Church elders.
Bible quotes are dime a dozen if taken out of context. If you take John 14:26, it is "clear" that we don't need anything but the Holy Spirit, not even the Bible, to know all things.
Obviously that is not so.
As for privileged authority in the Church, does not +Paul say
Not everyone in the Church can simply open the book and teach himself, just as God designated that women shall bear children and not men. It may not seem, "fair" but life is the way it is even if liberal Protestants don't understand it. :)
John's letter (1 John 2:27 DOESN'T say we do not need leaders and instructors -- It does clearly infer that the final authority for each believer is the indwelling Presence of the Holy Spirit.
God may orchestrate our completed spiritual instruction from many and varied sources -- church leaders, teachers/mentors, counselors, a tape series or DVD -- or a divine appointment on a street corner. But ultimately -- we are disciples of Jesus Christ; each with gifts, ministries and appointments to fulfill the high calling.
Have you ever noticed that the terms "elder" and "deacon" are never capitalized -- and remain much more descriptive terms of character and duties -- more descriptive than they are designations?
This ESPECIALLY includes the doma ministry gifts you have listed from Ephesians 4:11 -- apostles, prophets, evangelists, pastors, teacher...
These are mature spiritual gifts, and the completely configured gifts of the lives of men and women given for the ministries of the Kingdom of God (See Luke 4/Isaiah 61)
They are not inscriptions for anyone's T-shirt:
I am a(n) _______________ (fill-in the blank)
For all the zealous defense of "orthodoxy" and tradition here -- These same apologists seem to constantly:
1. Add to (or take away from...) the canon of Biblical truth,
2. Invent/re-invent more hierarchical religious offices,
3. teaxh and/or endorse un-Biblical (occasionally CLEARLY forbidden!) spiritual practices,... AND...
4. Additional rites, ordnances rituals and traditions that remain a very long way from and sound foundation in the simple Scriptural premises of the New Covenenant.
All of which begs the original question: