But you could disable it. The multi-window thing was something Delphi lifted directly from Visual Basic, and even VB dropped it (well, more like it got swallowed by VB.NET and Visual Studio.)

With monitors getting bigger we can abandon the multi window way and embrace something better, but surely not MDI which to me is even worse. Tiling is the answer: a giant single window containing the entire application, and a layout definition stating what section appears where and at what size (read: area percentage). Options to maximize the active area can be implemented, but the goal should be freeing the user from being forced to find and move windows from below other windows or partially gone out of the screen.

I think Visual Studio has the right idea with being primarily MDI but then all of the various windows can detach and float to other screens and wherever. I think if Windows would just render your desktop background on the MDI background instead of a solid color that would be a nice system setting.

I think maybe Delphi 5 was the first version where it stopped even being an option. I remember 3 was MDI and I'm surprised I never bothered looking for the option to switch it back.