I believe if you weight the ratings 100% based on the previous year then yes, it'd recalc, if you want your previous years of simulation to influence it, you can change the percentages around to whatever you want them to be.
There is also a setting to make players bad. And its default is like 20 ABs, where any player under that is thought to have "prospect" status of some sort and the game ignores stats. If you set it to zero, the game would see 10 Abs the same as 400, I'd assume.
