Terminally stupid, is something that counsel do raise in cases where the crime is so stupid in conception and execution that it makes the judge smile, but that's a rare case.
But chrisgel, you are right about proper burglars. Speed is of the essence, as is expertise in picking the target. No dogs in the house or at neighbouring houses, preferable to work in daylight, when people are at work, ideally a cul de sac or quiet street (no passers by) are the kind of things that the pros look out for.