And do you not understand they've had almost 16 years of "experience" in developing a gaming network infrastructure with the last 7 years of running of a multi-million player MMO.
At this point, I would expect them to do a little better. You know, people tend to learn from their mistakes - Blizzard doesn't seem to do so, every single launch they've had - let it be a beta or normal has been a complete and utter failure.
The StarCraft launch was pretty smooth. Every game has bugs when it launches, and just about every game has issues when it launches. The entire point of a stress test is to stress the servers so that they can get a better understanding of the limitations. More or less the servers are supposed to crash during the stress test. That's why there is ONE gateway in the stress test for the entire world. They want to see what happens when a heap of people from all over the globe log-in to one gateway. If you understand that and you still fault them for there being connection issues ... well then I don't really know what to say to that.