Too lazy to go back and read the original post, but my impression was it was advocating bringing a player up early enough to risk losing their rookie status this season because they could send them down next season before they had gotten a years service time. I leave it to you to distinguish between a year of service time and roy eligibility.
I might have inferred the poster's intention of sending them down next season. They might have meant this season, which, sure, it would work to retain rookie status, but you lose the advantage of bringing them up early to begin with. I also am too lazy to lok up Gil, and sad he won ROY for a different team, but i assume it falls in the latter category.. And i also assume there was a reason other than preserving rookie status to send him down, or he wasn't up so early as to lose it to begin with?
And my impression is last collective bargaining agreement also rewarded teams with ROY finishers? It encourages them to bring them up early in the season, but also increases the incentive to be deliberate about later cal ups.