[squarefoot]

GUI visual editors fail when they ignore problems that Borland Delphi and C++ Builder solved brilliantly well over 20 years ago creating an incredibly quick and productive workflow, and yes, they can become an absolute mess because of this. I can only dream of the day Lazarus (FOSS reimplementation of Delphi) will work with other languages beside Object Pascal.

[ptx]

Which problems are those?

One problem I usually have with GUI builders is that they generate huge and messy data files for the layout which can't be meaningfully diffed. Visual Basic is even worse because the form files are binary blobs. Lazarus seems to use fairly concise and readable plain-text files for its forms, although there's also some sort of binary resource files.

[speed_spread]

You'll have the same issue even with hand written code? I'd say the solution is that we need semantic diffing to show GUI changes.