You can successfully make a computer program play at a 2000 FIDE level (say), in that its win&#x2F;loss&#x2F;draw results will be consistent with that of a 2000 FIDE human. IPR is a good way of doing this in a quantitative way.<p>The interesting problem is to make the computer play <i>like</i> a 2000-rated person, not just <i>as well as</i> a 2000-rated person. I&#x27;m a big fan of Regan&#x27;s work, but I don&#x27;t think IPR on its own is sufficient to make the computer play <i>idiomatic</i> suboptimal moves.