kanibalkow, the issue with that is that Sjin is unreliable. He does a lot, but is all at random and not solid, so copying him is less fruitful than copying Billy and Baenarall. While Sjin gives more buffs than Billy, Billy is consistent. Sjin is certainly still worth keeping in the party for when his buffs happen to be on the useful end of the spectrum, but not worth wasting one of Mindy's two copy targets on.

If you have all his skills, decent gear, and put him somewhere where he is surrounded by crusaders, his buffs CAN be pretty huge. It is just the lack of consistency that is the issue. Not that I am complaining, though. That's just how the skill balances risk and reward.

Like I said, powerful but inconsistent. It doesn't NOT work, but there are better options.