Yes, but orders of magnitude less often than random members of the public "doing their own research". And looking at the consensus of the experts rather than individual experts the error rate is further orders of magnitude below that. You need to let go of the idea that information being a good basis for decisions means that it's "absolute truth", because only religion has that; what we have is some sources of information that are less likely to be wrong than all the others, and that's unfortunately the best you can get.
They didn't say you couldn't appeal a civil case. They said that ineffective counsel can't be the basis of that appeal.