i make sure the high potential play in the minors. so no idea on comparing playing time... but,
i'm fairly certain performance has between little and nothing to do with development in the minors. I'll spare any anecdotal tales. ratio of succes/fail seems about the same regardless. i promote based on ratings... even if they didn't acheive good numbers at the previous level. this sort of thing is quite common for me to see.
if it does add a wrinkle, which is certainly possible, it's likely some small bit beyond the resolution of the eye
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players don't get better due to performance... it's not logical. there nervous system doesn't improve, they don't magically gain muscles they didn't have from working out, they don't gain coordination or learn new mechanics through divine intervention after a good month. their work, preperation, and talent are what provide results when given enough opportunities to present itself.
that being said, a vidoe game is not real life. this would be a "gamey" aspect, if it were true that performance helps... and no big deal.
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as far as mystery? this is competition...vs humans i'd rather beat you than sit in awe of mystique of a RNG
if i were in an online league, i'd know the relative odds of everything possible to know from the feedback they give; limited only by my imagination/ability.
this isn't entirely unlike real life, either. statcast or w/e mlb's new data tracking system is called will provide some cool data once it accumulates. the curtain is about to be pulled back a bit. too much money in real life to worry about mystique, though... obviously a video game doesn't provide quite the same impetus.