Actually, I take that back—the other decision could have been sending him to Double-A.
While Harper may be the best prospect ever (or in recent memory), it's foolish to think he can defy the developmental realities that apply to any prospect.
Harper will spend the entire 2012 season at the age of 19. Do you know how many 19-year-old players have made a meaningful contribution in the majors since 1990?
The answer is none.
Alex Rodriguez had miserable and brief stints in the majors at 18 and 19. Adrian Beltre had a similarly unproductive half-season at 19. Andruw Jones struggled through his teenage years in the majors. And then there was the Mike Trout experience last year.
Highly touted prospects are still prospects. That goes for Harper, too.
All the tools in the world can't overcome a lack of development and performance. Harper was lacking in the latter in Double-A last year (his slash line was a sub-average .256/.329/.395). His A-ball performance was impressive, but it was far from awe-inspiring.
In the end, it was what it should be (in the context of expectations). Harper had a .979 OPS, showing impressive patience, but he still struck out a little too much. He also slugged the ball, but his slugging numbers weren't otherworldly—they were just really good.
Trout earned a similar level of recognition as Harper in 2010. He dominated A-ball with a performance nearly identical to Harper's, outside of the number of home runs (although they slugged nearly the same, Trout at .526 and Harper at .544). Then, Trout was inexplicably rushed to Los Angeles last year at 19, and he pretty much fell flat on his face, again, in the context of expectations.
And for what reason? I suppose it's nice to flash the ability to be a slightly above-average MLB player at 19 years old, but that's not why Trout plays baseball.
It's not why Harper plays baseball, either.
These are likely the two most talented position players (from a perspective of tools) who have existed in each of their lifetimes. These players play baseball to be the best, and they may be just that, because each has proved to be more than just an impressive skill set scouts can drool over. They've proved they can translate those tools to the field.
But, what each has failed to do is prove they can translate those tools (at least at their peak levels) to a Major League Baseball field.
Trout hasn't even touched Triple-A, where he should end up this year. Harper, as noted before, was a mediocre player in Double-A and also hasn't played in Triple-A.
So, the Nationals made the right call here. The worst-case scenario could have been rushing Harper to the majors and stunting his development. The best-case scenario could have been rushing him to the majors, where he would adequately perform at an obscene long-term cost.
No one needs to learn that Harper (and Trout) could be plus-0, but sub-1.0 WARP players at 19 years old—that's a given. What needs to be learned is whether or not these players can be 5-plus WARP players over their careers and compete for MVP awards year in and year out.
That means that all those tools need to be developed, and they need to prove their development through performance. Harper will have the chance to do so this year.