Very interesting take on all this democles - and it would make sense. Is this something you came up with on your own because of the way it "usually happens", or do you have some inside information?
I wish I did have some insider info, but no, this is just my best guess given the way the industry works.
Sadly, the games industry is going the way of Hollywood where the men in suits and ties so tight they cut off the circulation to their brain have all the power. Developers make the games, do all the real work, and then get punished like you wouldn't beleive if they fall behind. A lot of games get canned simply because they are a few months behind schedule. A lot of potentially fantastic games have gone this way. People in suits see only the dates and the current expenses, they lack the foresight to see the massive amounts they could be raking in if they let these games continue to completion.
In regards to the HL2 delay - I think vivendi had their own agenda all along. Even when Valve said September 30th at E3 Vivendi knew they were gonna aim for a holiday release which is why they gave november release dates to all the major distributors (and hence why all shops have dates around that time). Vivendi knew they had Valve by the balls and are quite happy to deprive their audience of the game for another 2 months just so they can get "record opening weekend sales". The publishers all want immediate revenue from their games, they aren't willing to look at it long term, even though a lot of games sell more in 3 years than they did in the first 3 months. HL1 was a prime example of this, but publishers couldn't give a toss. They know it's the developers that get the flak, not the publishers.
I wouldn't be at all surprised if after HL2 ships Valve announce they are cutting all ties with Vivendi. Much as Lionhead did with EA. The publishers have got to learn you can't scerew with the big developers and expect to get away with it. Lionhead's new publisher contract (if I remember rightly) gives Lionhead the rights to decide the release dates and what territories the games get distributed in. Hopefully more developers can wrangle deals like that and sort the industry out properly.