Problem with Delphi-style RAD tools is that there is huge step in complexity between things that can be done in the designer and these that can not. And this invites particular style of "programming" that consists of searching the internet for existing components and connecting these components together with horrible hacks. It is perfectly possible to write well-structured application in Delphi, but most are not.
[Edit: hit reply too soon] Tk model of UI programming does not promote this that much, because causing stuff to happen by writing code is the default way. Also Tk-style approach of writing GUI definitions in code and letting the toolkit to deal with details like positioning (in fact, using HTML for UI is mostly similar) is more productive.
I don't really want to get into a long-winded discussion, but (a) the GUI definition in Delphi is also code (specifically: there's a declarative syntax for constructing a tree of components with property values); and (b) positioning is handled by the VCL. Typically you specify things like alignments and borders in the designer, and the VCL takes care of keeping things positioned.
I really wish HTML was as easy to design with as the VCL designer. Trying to e.g. create vertically centered children is far, far easier in the VCL than in HTML + CSS.
[Edit: hit reply too soon] Tk model of UI programming does not promote this that much, because causing stuff to happen by writing code is the default way. Also Tk-style approach of writing GUI definitions in code and letting the toolkit to deal with details like positioning (in fact, using HTML for UI is mostly similar) is more productive.