I believe about 90% of the tasks were estimated by humans to take less than one hour to solve, so we aren't talking about very complex problems, and to boot, the contamination factor is huge: o3 (or any big model) will have in-depth knowledge of the internals of these projects, and often even know about the individual issues themselves (e.g. you can say what was Github issue #4145 in project foo, and there's a decent chance it can tell you exactly what the issue was about!)
