I just found something else cool about 3 year recalc. It gives you access to players the year before their actual debut. For example, Oscar Gamble is a 17 year old (18 very shortly) in my amateur draft this year, and he didn't debut until he was 19. Very cool.
I wonder if 5 year recalc gives them to you two years early? Not that I want to try it because I prefer 3 year recalc, double weighted for the current year. That puts 50% emphasis on the year in question and 25% each on the sandwiching years.
EDIT: This is not universal. Some players are debuting when they should.