Would you kindly either take your discussion to PM, or create another thread, because right now I cannot seem to find any useful posts that I might be looking for - rather, just a lot of elongated posts by yourself arguing the intricacies of DRM / non-DRM and the likes.
Whilst I do find the subject of your discourse relevent to the thread (of course!), it is currently very much in the way of the thread having any real use to me - moreso because of the very broken GOG search function.

Thankyou! :)

Going on 10 hours now, this has clearly entered trolling territory.

I know of that, but of the CEG aspect, how would that differ from the existing situation with third-party DRM?

They don't want you to think you don't need Steam evar.
I can see why some would say yes, because it ties it to an account, but I say no. It's like sending someone a letter: you need an envelope, a stamp and a delivery method so that the one person receives it. If you could buy the game more than once and send the files to someone each time, you'd be in total control, though. They'd rather have each person open an account.

As I don't own that much games (or better: can't afford) on Steam, I use Steam Family Sharing (now: SFS) to install and test games from friends.

But this rises a question: Are the results from SFS the same as testing your own games?
In the past it happened that some games tested with SFS required Steam when they normally shouldn't. The game in case was VVVVVV, but now it also works fine with SFS. I'm puzzled...
Well, I went along with the following rule: If a game works with SFS, then it also should work as your own game. If it doesn't then you can't say anything about the status of the game.

What do you think? IMHO SFS is a interesting matter (and convenient for testing more games).

To make this post useful, I tested They Bleed Pixels and The Yawhg. Both don't require Steam to be played.

Good rule, I think that's reasonable. My general rule is that if it's an old game, then it's likely to be steam DRM-free.

I think it would be a good idea to make a note of that in the notes sections, though; just a small "tested via Steam Family Share" or something. In case there's a discrepancy in the future, someone would be able to discern the reason. It's up to you about the note, but that's what I'll do if I do this in the future.

The fun thing about DRM is that there is no universal definition on what DRM is, so the above is your interpretation of the term. It is by no means universal, nor more or less correct than anyone else. It is possible for someone to define DRM as everything digital with some form of restricting access after purchase, and as such not limited to schemes needing internet for verification. By the latter, a CD key for local only, or indeed copy protection, can be defined as DRM. You do not think this is the case, but it does not mean that it is wrong either.

Wow, I haven't been here for a bit. Anyway, I just added Astebreed to the DRM-free list. That company always makes their games DRM-free on Steam, it seems.

Another example (bugged, though) is Tropico 3. The game refuses to normally run, till you delete a cfg file and when it does eventually run after the file's deletion it asks for a serial code; the very same serial on your account.

Evochron Mercenary can be run without Steam. The Steam "CD Key" can also be used on the stand-alone, DRM Free version from the developer's site.

http://www.starwraith.com/forum/viewthread.php?tid=9596

The serial on the game download page is unique though, not the one installed by default.

Useful threat indeed. Ops, thread.

Same case with Neverwinter Nights 2. The game installs itself with a generic key, but to play multiplayer, you have to use the key on your account. That would normally be the case with Tropico 3 (the serial is only used for high-scores or achievements or something like that), but thanks to a bug, you are forced to use it to play the game.

Well I'm arguing AllCD keys are DRM so I'm not going to make an argument the opposite but all cases I know of on GOG that have a CD key are for the online component of a game. Howrver the exact mechanics work will depend on the system implemented for each game. The basic fact remains it's for online verification not offline gaming, with some games these are likely unable to be separated.

There will always be an exception due to variations in how specific keys work but the core reason of being for online access is the why any CD key for games on GOG.

This is all a side issue to my reason for mentioning CD keys in this thread though, in an effort to get back to that unresolved issue I will try again.

Some games listed as DRM Free on Steam in this thread, do require a CD key (Fallout 3 does) when copied after applying that key (often done automatically by Steam) the game should run fine without said key. It should be noted in any list of games that run without Steam if a CD Key is used and a recommendation to record the Key from the Steam Client.

Knowing a key may be required can save a lot of hassle if it ever gets corrupted or deleted from the registry. IF Steam does ever cease to exist it will be to late to get the key then.