Interesting idea, but I can’t recall any indication in the script or the novel that Artoo was piloting the pod.
Don’t know about the script or the novel, but this was established in the radio drama. It actually does a good job at evading some of the plot problems (another being R2 sabotaging Skippy on the sandcrawler), while possibly introducing others.
Brian Daley really thought out all the angles. 😃