1. Reformed Presbyterians?? Please expand on this term. Are you referring to Reformed Presbyterians as a denomination? If so, which one?

Actually my mistake, because Presbyterians are supposed to be Reformed. Perhaps what I am trying to say is Presbyterians who claim to have a high view of Scripture. I.e, are not part of the PCA, who have given into liberalism. Hope, that helps?

2. This is not something new. I remember it being expressed nearly 50 years ago by some. The view is based upon such passages as Acts 21:8; Matt 28:18,19, Eph 4:12, and 2Tim 4:5. True, there are specific people who are gifted and recognized as such who are commissioned to do evangelistic work, e.g., missionaries. But the typical Christian can and should make known the Gospel when given the opportunity... as a Disciple of Christ. Admittedly, the average Christian is quite limited since in our day, they are woefully untrained and ignorant of even the great and fundamental doctrines of Scripture. Are you doubtful of this? Just ask someone who professes to be a follower of Christ to explain the doctrine of justification in simple terms. I am not suggesting an answer such as the once popular ditty; "Just as if I'd never sinned" as an acceptable response. Or, how about explaining the Fall of mankind and its results? Catch my drift... snowbank? So, for the average professing Christian to faithfully present the biblical Gospel is typically a rare thing, I say with much consternation and sorrow. But again, may (permission) vs. can (ability) a Christian 'share the Gospel' to the world; Yes, for I see no prohibition or restriction on who may speak the truth in love to all as God provides the occasion to do so, whether at length or in part.

It should not surprise me that this is not new; but the funny thing is, even when I was an Arminian I was taught that we should as Christians spread the Gospel. I can remember when I first believed, how anxious I was to tell people about what the Lord had done for me. I really had no fear of man at the time and sometimes the Lord even in my naivety used that. For example, I remember back when I was about 20, sitting around a camp fire, late at night talking with a guy I have never met before. We were discussing life and that conversation sort of naturally went to the Lord. Some of the people sitting around the camp fire left and if I remember correctly they may have done so because they wanted no part of the conversation, lol.
Yet the person seemed to be drinking everything I said in. I had only been a Christian for a few months, but I literally loved reading and studying the Bible and much of what I said flowed from that. In the end, I remember the young man thanking me for the conversation and added that he was brought up in the Church, but had walked away. Yet, because of me, might just go back.
I could tell you a few other stories like that, however the point is. The Lord used me, simply because I was a willing vessel and I wanted to show my gratefulness to the Lord for what He had done for me. Nobody told me not to evangelize and if they had, I would have been shocked.
Some of my theology was a bit off back then, but I was sure hungry for His Word.
In some ways, I miss my zeal that came with my new found faith.

You asked if I doubt that the average Christian is woefully ignorant and untrained. Sigh, I donít doubt this at all, I have had enough conversations with Christians to know this is true.
This is one of the reasons I am a big fan of Reformed catechism, which are a great tool in teaching doctrine.
To quote CH Spurgeon:
I am persuaded that the use of a good Catechism in all our families will be a great safeguard against the increasing errors of the times, and therefore I have compiled this little manual from the Westminster Assembly's and Baptist Catechisms, for the use of my own church and congregation. Those who use it in their families or classes must labour to explain the sense; but the words should be carefully learned by heart, for they will be understood better as years pass.