> you know you don't need tell everyone how you have palter's vlm to look at rel-8-5's sysdcl which has been leaked and hosted on public sites since forever

I'm not sure what you are talking about. It's not related to what I wrote.

> how thick a layer dynamic-window is on top of tv? answering that question require systems level knowledge and investigation.

Dynamic Windows introduced a new UI look and feel, different from the old "static windows". DW has new APIs even for reimplementations of old UI features from TV , like the new drawing interface in the graphics package, which replaces the old TV flavor messages, with generic functions. It has also a lot of new features, like the presentation system. Later applications typically will use the new DW interfaces and new features. Both DW and TC are documented in "Programming the User Interface", with DW providing much of the high-level application window features, described in the first chapters.

There is another version of it, in another implementation, which is CLIM, which is then based on CLOS. Even later applications were thought to use the CLIM interfaces, to be able to write portable user interfaces, able to run on various other Lisp systems. Both DW and CLIM are substantially different from TV. Neither DW, nor CLIM are in the MIT software.

Other symbolics extensions are of similar nature.