"The best example was the race at Mid-Ohio," admitted Barrichello. He had started in 13th place but finished in 15th, while Kanaan started in 18th and finished in sixth place. "Tony set off behind me, but he was far ahead of me at the finish. This shows that I still have much to learn."
Inevitably there have been less than favourable comparisons between Barrichello's maiden season and that of another rookie entering the series after years of sportscar racing in Europe. In the single-car Schmidt-Hamilton Motorsports operation, the impressive Simon Pagenaud has finished in the top ten seven times - including three podiums - to put him ahead of even Tony Kanaan in the drivers' standings.
With Barrichello making noises about not seeing his F1 career as totally over and done with, the question will be firstly whether he continues in IndyCar in 2013 - and if he does, whether it will continue to be with Chevrolet-powered KV Racing.
Barrichello was at pains to praise the "incredibly friendly working atmosphere" at the team. As well as enjoying working with his "brother" Tony Kanaan for the first time as a team mate, Barrichello said that he had a "very good" relationship with the team's third driver EJ Viso and regarded team co-owner Jimmy Vasser as "my teacher."
But Barrichello also admitted that "something is not going right in the team." Speaking during the most recent race weekend at Mid-Ohio Sports Car Course at the start of August, he explained: "I knew it [moving to IndyCar] was a learning process and that's what I'm doing, but I still don't have a basic setup that I'm comfortable with
"It's like walking on a tightrope. The balance is very tight, it is what it is. I'm consistently getting better, but unfortunately the car is still not where we would like it to be," he said. "Our results have been disappointing and I would like a competitive car."
Barrichello's concerns appeared to be somewhat echoed by Kanaan: "Our qualifying results have been very, very poor, so there is something in the setup," said the veteran of 17 seasons of US open wheel competition. "We aren't winning because we aren't qualifying well."
"We're all disappointed because we haven't run better," agreed KV Racing team principal and former Champ Car driver Jimmy Vasser. "We need to put our head down and work.
"We've had our ups and downs, we've been quick in practice and the race, but we need to get qualifying working a bit smoother," he added. "It's a little bit of finding the harmonic balance, but it's been elusive."
For his part, Vasser made it clear that he wanted Barrichello to stay with the team next season. "We've got an investment in Rubens, we want to keep him and we've got people in Brazil right now trying to sell sponsorships," he said.