I come with more data. Season 4 with Clemson. I have won 3 Natys in a row. I have 18 total players leaving for the draft. 4 are seniors and 14 are underclassmen with at least 3 years of eligibility. Out of the 14, 10 have "none" for persuasion chance to stay, while 4 have an option to persuade. With all of the perks in persuasion, I am able to keep the 4 with a chance. With the exception of one player out of the 14 all of them have at least a 90 over or higher with the highest being a SO(RS) 99 OVR QB who started 1 season. The anomaly is my backup running back who is overall 88 and set for the 6th round and has "None" persuasive options.
Let's put this in perspective:
If I did not have persuasion abilities this is what I could lose in one season:
Offense: Starting QB, Best 2 HB, Best 2 WR, Best TE, Best Center all are underclassmen
Defence: Starting Edge, All 3 starting Line backers, 1 CB, Both starting Safeties, all are underclassmen.
If you throw in the transfer portal, which I have capped at 12, the total players leaving in the offseason without persuasion attempts would be 30 players total.
If I had the transfer portal set to default 20, I could be losing as many as 38 players in one season, which is more than the 35 I can recoup from recruiting in one year.
Although not completely unthinkable, it is definitely challenging. Hopefully, this will not continue every couple of seasons.