I have not attended any of the numerous shiurim that have sprung up to preach the message of bitachon during economic downturn because I don't know if there is much to say on the topic. Obviously, trying times demand bitachon -- knowing that is no kuntz; the kuntz is implemeting it. If someone has heard a chiddush in this sugya, I would be interested to know what it is.
One refreshingly realistic approach to this whole parsha that I saw recently can be found in the Sichos MoHaRaN (Avodas Hashem #55). R' Nachman writes that bitachon is a wonderful thing to have, but it is even nicer to have a steady job. Quite a mouthful from a tzadik who we usually associate with other-wordly spirituality and not Torah im derech eretz ideals! Of course, Rabbi Nachman of Breslov was not anti exercising bitachon. But, as the Sichos Moharan explains, exercising bitachon is a very demanding avodah. R' Nachman does not just mean demanding in the practical sense, e.g. a person who is out of work is not going to write out a check of tzedaka when he has no source of income. R' Nachman means bitachon is demanding in the emotional, psychological, and spiritual sense. Ask anyone out of work and they can tell you how psychologically trying it is to remain hopeful and keep a seder and not fall into despair while trying to remain financially afloat and find other work. All that energy that goes into maintaining a sense of bitachon has to come from somewhere. Inevitably, it is a drain on other areas of life and other areas of avodas Hashem. A person's head is obviously not into a Keztos or R' Akiva Eiger when he doesn't know how to pay his mortgage. A person's mouth may say "l'shem yichud", but his mind and heart are on the electric bill or next month's tuition that he can't pay.
It is almost too easy to give a shiur or personal advice extolling the virtue of bitachon without really having a sense of the emotional trauma that people may be going through. That, I think, is what Rabbi Nachman is trying to warn against (and if there was ever a tzadik who was attuned to souls in crisis, it was R' Nachman.) There is no magic "bitachon switch" that can be turned on to continue life as normal despite crisis -- it would be foolish to think otherwise or for anyone to give a shiur or offer advice suggesting otherwise. At the same time, we need to realize that Hashem ultimately is the one assigning a particular avodah to each of us. It would be better to not have a crisis and to be able to devote one's spiritual energy to other areas of avodah, be it learning, be it chessed, etc. But if Hashem forces one into a situation where greater bitachon is demanded, then it is Hashem's will that a person devote his or her spiritual energy to work on this midah even if it poses obstacles (and it will!) in other areas of avodah.