Hi,
...... . I don't think it will let more than one copy of 'your' game to be used at one time.
This depends on the Game ..... better .... on the implementing of the DRM ...
I have games .. that only need to start over steam, no change if i have Steam in online or offline mode.
If you start an game in offline mode, steam cant check if you run another instance of your steam account on another PC.
(you can only have your Steam account ONE count online at Time - if you try to go online with the same account on another PC - the first online Steam client will then be closed)
Then it gives games . that need to check periodical that the DRM is valid - you musst go all 2-4 weeks online ... between this - you can play flawless offline.
The games that really NEED an online steam client to play are very rare ...
But -> it gives the other side - Games that have no interest after install on steam online/offline more but connect to his own server to verify the DRM (most over unique keys) and here you musst really buy, one copy for every PC.(Wargame series or Giants games)
So it is ATM not know, which DRM mechanic HOI IV will have IMHO ...
Regards
R-TEAM