I strongly disagree with those definitions. A performer is simply one who performs and utilizes many performing aspects, not just playing the piano. A technician is someone who plays the piano but does not make music.
Well, I didn't want to mean that, so let's say the next:A person with natural talent, this person can be an amateur and doesn't play as teachers and the sheet says, but this person plays wonderfully in front of an audience, and loves what he/she does. Playing depends of the mood he/she is.The other one, practice hard, plays with accuracy, follows the teachers instructions and doesn't get out of the piano sheet, but his/her music lacks something, and he/she has a love/hate relationship with the piano.