Staggering population is dumb unless it means 'we won't let more people than the server capacity in', in that case that's common sense. Usually on a launch the login server gets hammered since no login server is designed to handle nearly 100% of its population trying to log on at once, but that's okay because when 100% of your population is trying to log on, you hit your server's capacity cap pretty soon anyway so it really doesn't matter if the login servers are slow or dead if there's no room for them on the server anyway.
The whole way SWTOR is been handled makes me think either the guys behind it are total newbs or they've a way to make the most mundane tasks in MMORPG sound like a revolution. Launch day crowd is almost like a rite of passage. Unless you've some really special designed hardware that's designed to fail when 300 people log in your newbie zone (and you actually have to try pretty hard to do that, EQ1 could handle that many in a zone easy), there's nothing particularly unusual about being swamped on the first day or even month. If people didn't enjoy having your average mob stay up for 1 second before it's killed by 10 guys, they wouldn't be playing your game in the first place (not to mention there's always servers with low population to move to no matter how popular is). Yeah they're going to go to the forums and post how there are 10 times the players compared to mobs, but that's like complaining you lined up 5 hours for PS3 launch even though only 2 other guys were waiting total.
As an aside, having various degree of early based on when you pre order is just dumb. It's not like the early access is really that big of a deal but it'll make people angry for no reason. I have no problem if they give the guys who paid $150 for the super deluxe version, or even the $70 deluxe version some kind of advantage, but if you got the cheapo $50 standard version it should be the same no matter when you preordered. I think most places lets you cancel a preorder at no charge anyway? So it's not like you get more value out of someone preordered early unless getting that $5 3 months earlier is really that important for cash flow.