The main reason Hansen’s 1988 warming projections were too high is that he used a climate model with a high climate sensitivity, and his results are actually evidence that the true climate sensitivity parameter is within the range accepted by the IPCC.
There is no consideration of the possibilities that (a) one or more other parameters were wrong or (b) the model — aside from parameter values — is wrong (e.g., it oversimplifies). Surely you are joking, Mr. Skeptical Science.
Thanks to Phil Price.