I always thought the take your daughter to work day thing was supposed be hinting at how Chell originally got there. GLaDOS probably took all of the daughters and told then that their parents abandoned them...
also why would Alyx (Vance) be at Aperature's take take your daughter to work day...
Ya I was wondering exactly what they meant by that as well. I was thinking they meant that one door was actually still a portal instead of a door and so if u noclipped through the wall next to it you would not end up where you might think...
Im pretty sure valve were gonna put all the content of episode 1,2, and 3 into one game and call it Half-Life 2: Aftermath (i read an article about it in PC gamer in 2005), but then they decided to go with the episodic content for faster releases and so they could improve the engine as time went...
I think the OP asked this question because console versions of games tend to have less features of this kind.... like Oblivion for example, on pc you could pick up and object and throw it around and what not without it actually being in your inventory, however on the 360 there is no such...