I don't think that's fair, as there are players who make significant jumps between their first and second full MLB seasons. Robin Ventura made significant strides between 1990 and 1991. July 1991, in particular, was the month that he finally seemed to hit his stride, culminating in one of the most exciting games in White Sox history.
Now, munch, watch carefully:
That has about zero relevance as Robin was picked by scouts to be pretty dang good. The book on Viciedo was (and always has been since his first professional season in the minors) that he'd never see the ball well enough to be an everyday player. Pretty much the only people saying otherwise all these years has been the White Sox organization. Maybe they're right and everyone else is wrong...but I really don't think so.