What happens when a HL2 patch breaks something....Since steam is a requirement, the patch is forced upon you, and you're fucked.
Not true.
1. Open up the Play Games Window.
2. Right Click on Half-Life 2.
3. Select Properties.
4. Go to dropdown box labeled "Automatic Updates"
5. Select "Do Not Automatically Update This Game"
6. Click Close.
You can now patch when you want to and not when steam wants you to. Of course you can't play multiplayer unless you update but that has always been the case anyway.