As far as I understand, Eliezer doesn’t claim that plans are generally very useful for making progress in solving problems. Trial and error usually works very well. But he also says that trial and error will not work for the alignment problem; we have to get it right the first time, therefore detailed plans are our only hope. This isn’t a overconfidence in plans, it is just a high confidence that the usual trial and error approach can’t be used this time.
As far as I understand, Eliezer doesn’t claim that plans are generally very useful for making progress in solving problems. Trial and error usually works very well. But he also says that trial and error will not work for the alignment problem; we have to get it right the first time, therefore detailed plans are our only hope. This isn’t a overconfidence in plans, it is just a high confidence that the usual trial and error approach can’t be used this time.