The title of a recent post by Jonathan Merritt seems to be attempting to answer the question, "how many assumptions can be squeezed into one title?" rather than the one posed in his September 11th "Have evangelicals diluted Jesus’ radical message?"
By the title you would have assume: 1. Jesus existed, 2. there is a single interpretation of who the Jesus figure was, 3. that it is possible to know which interpretation of the Jesus figure is accurate/correct, 4. that those who identify as "evangelicals" among Christians are incorrect or inaccurate in their views of Jesus, 5. that there is a clear "message" attached to the Jesus figure, 6. that message is uniquely Jesus, and 7. that message is "radical."
It is possible I may have missed a few assumptions. Even so, that's a lot crammed in one short question. And, yes, they are entirely assumptions. There is no sound evidence to support a single one of the assumptions enumerated. In point of fact, a few of them are refuted by Christians themselves. The overwhelming majority of religious scholars who happen to also be Christians concede that there were any number of itinerant preachers and reformers roaming around the middle east before, during, and after Christ's supposed life-time. Many of them conveyed very similar ideas and practices. John the Baptist, an equally historically suspicious character, is said by many Christians to be a precursor to Christ. According to scripture there were even groups of theists who mistook John for the Messiah.
Then, of course, there's a problem with characterizing Christ's message. I have heard many Christians reference Mark 12:17, "And Jesus answering said unto them, Render to Caesar the things that are Caesar's, and to God the things that are God's. And they marvelled at him.", for a variety of purposes. This is just one of many that I would personally interpret as a very conformist stance. Last I checked conforming to conventional norms is the exact opposite of being a radical. But, once again, this is just one possible interpretation. There can be no definitive views on Christ or Christ's message since the only available information is highly dubious and completely subjective.
Basically, if you adhere to standards of historical research the answer to Merritt's question is no since Jesus did not actually exist and therefore did not have a "message" at all. If you take a theological approach, no discernible standards at all, there can be no answer.