I was the human player in 2001 (maybe cause I am 6'5'' tall) and in some matches in 2000. I think I was very useful last year cause I filled the goals in almost every match.
It's really a great experience to be one of those in the playing field.
Last year in the Nationals I threw a ball when the robot was already pulling the goal back, so I missed it, and that ball gave me a serious headache: it went to the right, stopped a bit, came to the center, went over the bridge, touched a robot, rolled to the top of the wood field divisor, fell down to the other side and when the robot was about to balanced the bridge, the ball went under the bridge!! That was one chance in one billion!!
I'm sure it was Murphy's ghost leading the ball under the bridge to make sure that "if a bad thing may happen, it WILL happen" ("Murphy's Law").
This year Manoel is our "human player", but what he does is to operate one part of the robot and help the team with his endless knowledge.

The official robot operator (Luiza) has scored more balls than him this year, but in 2000 he won a game for us by shooting balls.
I think human players are really important, but I voted for "we need 3 operators".