Sadly (IMHO), Graphisoft went down the GDL scripting route to build complex forms, rather than using graphical modelling techniques.
While the programmer may find it a more powerful technique, I for one don't have the programming skills to describe the geometries I wish to achieve.
This lack has been addressed by various add-ons that are available, e.g.
-zoom gdl (by abvent makers of Artlantis)
-GDL toolbox (was free but discontinued after AC9)
and more recently
-Maxonform
(to name a few)
Aside from the obvious issue (increased cost) there is also one of availability (development seems to lag major AC releases).
In other words, this issue remains.
