I already have gog version preordered
but now I'm interested how it really works on steam. I have quite a few games on steam and some of them are from that list, actually.
Well, I can give you an example.
Let's take the little game "A Virus Named Tom". It's completely DRM-free on Steam (initial download excluded). If you want to play the game on another PC without using Steam you just have to do the following steps.
1) Download the game via the Steam client on PC A.
2) Start the game once on PC A because Steam loads some needed files not until you start the game for the first time.
3) Exit the game.
4) Navigate to the game file in your Steam directory (.../Steam/SteamApps/common/A Virus Named Tom) and copy the whole file to a USB stick.
5) Copy the file to a random destination on PC B (where Steam isn't running).
6) Start the game by clicking on the AVNT.exe in the directory.
7) Enjoy the game without using Steam on PC B.
Of course the same works on PC A. You can close Steam after you downloaded and started the game once. The game will continue to run without any problems.
A Virus Named Tom by the way offers Steam achievements, Steam cloud saves, Steam leaderboards and Steam trading cards in case you use the cient for playing. Being DRM-free doesn't seem to limit your freedom as a developer to implement basic Steam functionalities.