Solaris, I can't tell you whether Darden MBAs were specifically dumped for Duke MBAs.
What I can tell you is that every bulge bracket bank has its own set of recruiting schools known as the core. About 95% of available seats get filled up by students from these schools. Duke is almost always part of this core (I've seen the recruiting process at several banks), while Darden isn't on every list that Duke is on.
Honestly, when it comes to recruiting in finance, it makes very little difference how good the classes are or the progress that the school has made. If you attend a school that has stronger relationships on Wall Street then many more doors are open for you.
Duke has been a strong name for years... Although Darden is highly regarded, it can't compete with the relationships that Duke has built over the years. After working in finance and going through the grueling recruiting process, I can tell you that putting Duke versus Darden is like putting H/S/W versus Ross.
My 80 or so person analyst class had 7-9 Duke grads while only 1-2 UVA grads. If this is the typical recruiting pattern that happens year after year then you can imagine the comparative magnitude of the network that Duke has built in finance over the years. Honestly, IMO, if you got in at Duke and Darden... I think you'd be crazy to go to Darden if you are trying to get into finance (all else equal).
Don't get me wrong, Darden is a great institution and it is tough to get into. I am not affiliated with Duke by any means, I just think Duke offers more opportunities in finance.