As one of the original Thief developers, I respect and appreciate this video - many thanks! I also agree that a lot of design values and mentality were more to my tastes in the 90's than they are in games today and that there was a current of innovation that has been since neglected (asides here: the indie games community has to a good degree kept this alive, and also if you can find it check out Clint Hocking's excellent GDC talk comparing the Ultima series to modern gaming). That said, I did want to offer a few observations from having been a Thief developer: some things that drove us included economy (we had limited budget, schedule, and resources) and therefore orthogonality (why make a similar tool/feature when you can make one with a distinct purpose with no overlap), immersion (what would it be like to really live in this world, in this character's shoes and how can we best convey that with our limited tools), focused direction (do one thing and do it well; note that Thief's director, Greg LoPiccolo, next went on to lead the development of Guitar Hero), a belief in the medium (video games are a distinct form of art/expression, how can we emphasize what this medium does best) and therefore player ownership (how can we allow our players to feel like what's happened to them was a result of their own choices and actions and not something we baked in advance for them). However, we weren't quite as principled and flawless as this video makes us out to be. For example, I think we would have liked fancier, more dynamic maps if we had the budget for it - though I suspect that ours still would have been a world building tool and not a minimap. We might have added better training and mid-mission cinematics to expand our storytelling, although I suspect those would have erred on the side of not interrupting the player's experience. That's why I started the list with "economy;" Thief was razor sharp in part because we didn't have the budget to bloat it out with surplus features, and it's to our credit that we focused what we did have in the right directions. If there's other designers reading this: you too can get this right! And if you make some mistakes, that's okay! We did too!