One of the great failures in human thinking (including draft analysis) is reasoning from analogy rather than first principles. What this means in draft lingo is that players are compared to superstars, implicitly setting an association between the prospect and the superstar. For example, Saquon Barkley is "compared" to Barry Sanders and David Johnson. Which makes it seem like that's who he'll be - an NFL superstar. This is a cognitive bias known as "anchoring". And its why this board and every board (and probably most NFL draft rooms) are filled with groupthink and poor decision-making.
But smart people (not talking about myself) reason from first principles. First principles are basic, self-evident assumptions that you can use reason to build from. Peter Thiel and Elon Musk are famous for talking about the importance of reasoning from first principles. Daryl Morey, famous NBA executive, talked about how he banned player comparisons for this reason.
When we evaluate prospects, we need to throw out the player comparisons. We need to reason from first principals. What's important for an NFL RB? What skills are essential? What skills are rare? etc. Player comparisons do far more harm than good. And we know this just by looking at the draft itself: almost no one lives up to their player comparison.
That's because most players in the 1st round will bust. And there's no such thing as a "safe pick".
Go look at any draft. Here are the 2012, 2013 and 2014 drafts:
https://en.wikipedia.org/wiki/2012_NFL_Draft
https://en.wikipedia.org/wiki/2013_NFL_Draft
https://en.wikipedia .org/wiki/2014_NFL_Draft
First, Matt Kalil, Mark Barron, Andrew Luck, Eric Fisher, Jonathan Cooper, Jadeveon Clowney, and Sammy Watkins were all supposed to be safe picks. Especially taking a SS (Barron) and G (Cooper) that high. We naturally think that if you're drafting a position much higher than normal that the player is that much better. But often they're not.
Second, the 2nd player taken at a position is often the better player. Now, this could be in part because they go to better teams (drafting later) who know how to maximise the skillset. But the draft is littered with the 2nd player being better. Too many examples to list just from these drafts, but: H Smith/Barron, Cox/Poe, Gilmore/Claiborne, Mack/Clowney, Ansah/Jordan, Matthews/Robinson, etc. etc. etc.
Third, all positions have a high bust rate early in the 1st. And RBs have the highest bust rate amongst all positions.
tl;dr
There are no safe positions. As good as Barkley or Nelson are, they are both likely to be mediocre players or busts. But picking an OL has a higher success rate than an RB. Most of these players taken in R1 will not be very good players. There is no such thing as a "safe" pick.
