With netinst cd, you can just install KDE no other gtk-gnome stuff.
When you start installing, installer asks you what package groups to install, choose the standart system and deselect all including Desktop. Installer will only install the core system. After installation and rebooting, system prompt you for username and password.
Become root and run:
apt-get install x-window-system-core kde kdm
That's it. You have your "just" KDE desktop. Reply to: