The only thing that'll make an executive's eyebrows rise higher than an impressive exit velocity is a massive leap in the power metric year-over-year. When a prospect's raw tools shine, scouts make a note. When a prospect's raw tools progress? He's both talented and coachable.
Those gains can be even more tantalizing when they're paired with a still-teenaged prospect growing into his projectable body, rather than overhauling his swing. If such a big leap is plausible naturally, what might come next, once the player's approach is streamlined and honed?
Baseball America recently published an examination of the prospects throughout the minor leagues who registered as "90th percentile exit velocity gainers" this past season.