Thanks for the advice. Even though I much prefer GOG where running games DRM-free is officially supported, I am not against finding out ways how to make my Steam games Steam- and DRM-free.
However, I kinda missed the point: why should this proposed process be followed, instead of the earlier "just copy your Steam game to another PC, and run it there without Steam client"?
Wasn't it so already earlier that Steam games without CEG and 3rd party DRM should be fully portable, ie, just copy the game directory to another PC, and run it there (without the client)?
Also I didn't get the point that moving the games from one Windows version to another may require going online with Steam. That sounds like an odd restriction to me, for a supposedly "DRM-free" game. The earlier way (ie. copy only the game directory, not the whole Steam folder) doesn't have this restriction, right?
Most Steam games actually can't just be copied to other machines and played; the links I provided in the first post just list the Steam games that are inherently DRM-free and that only use Steam as a delivery service. Most games on Steam, however, like The Evil Within, Deus Ex: Human Revolution, all the Resident Evil games, all the Sonic The Hedgehog games, etc., require the client to be running and to be logged into an account that purchased those games. Any games NOT on that list of DRM-free Steam games will require the client in order to even launch the games at all. This tutorial is here to help you run those games, the Steam titles that absolutely require the use of the client.
As far as the upgraded Windows version goes, that restriction is simply so Steam can actually run in an updated environment. If you download the necessary files that Steam prompts you to download, then you never have to do it again from any PC-to-PC transfer. There were just some incompatibilities between Windows 7 and Windows 8 that Valve needed to fix to have an existing Steam setup function properly.
About time someone highlighted the distinction between Steamworks and CEG! In other words Valve actually has two seperate sets of DRM?
That's exactly right. There's the regular Steam DRM, which just requires a game to launch while the Steam client is running, and there's CEG, which actually generates system-specific files that have to be redownloaded on each machine that runs the game. CEG games can't be copied and pasted and expected to work, because even though you still have all your license files, the actual program files will be different on every PC.
Steamworks just means that a game utilizes the Steam system's features, like achievements, online multiplayer, leaderboards, and possibly Workshop support, and as games like Super Meat Boy have shown us, you don't need to require the Steam client in order to implement all the Steamworks features that the platform offers.