I'm not so sure. A few years ago in university I took a stats course (offered by the maths department) that had twice-weekly mandatory labs where we learned and used R. Most people in the course were not programmers at all, and I ended up helping people most of the time during the course.

R is really weird, but non-programmers are typically unaccustomed to precisely typing non-english into a computer. They aren't trained to quickly spot syntax errors or grok error messages.

My own experience was that I came from statistical languages like SAS, bounced right off R, ended up learning Python and then came back to R and was like "ohhhh…"

It's an odd language, that makes assumptions neither group really hold dear to their heart, but it's also intensely useful.

For someone with a programming background, this is one of the best introductions I've seen: http://medianetwork.oracle.com/video/player/2623621262001

That's a very good way of putting it!