Here's a process I encountered; three manufacturing departments, set up in series, the first feeding the second, which subsequently fed the third, they were in complete disarray. Each department was a silo with a decades old MRP system driving them. The organization was structured around MRP. I didn't need a value stream map to see the problem. It was obvious. It needed a make over, but of course no one was ready to rearrange "the furniture".
My solution was to leapfrog the MRP system and use Excel and SharePoint to create a job based scheduling process that flowed material in small batches from one department to the next. The improvement was huge. Management gained control of the operation, it no longer controlled them. WIP lowered by over 60%, customer past dues were almost eliminated. People were no longer making parts to sit on a shelf for weeks.
My point here is that many Lean pratitionaers would insist on a value stream map to find the solution to this problem. I didn't bother, I could see what was needed. The next phase, now that the organization can see the benefit of flow, might be rearranging the furniture to take things to the next level, (that would have been premature before changing the scheduling system.) One more point, I couldn't possibly see all the problems that would be encountered along the way, but I had confidence we would find a solution to each as we implemented the changes, and we did.)
I recently read Peter Diamandis' post "Problems are Goldmines". In it he talks about turning around a bureaucratic and inefficient hospital and the approach he would use. He doesn't mention Value Stream Mapping or Lean at all. He takes a straight forward common sense approach to rethink everything they're doing. Does it work, well I can't say, he doesn't present results. But he has created enough change in the world that I would not doubt his advice, Peter Diamandis.
Many Lean practitioners would think its heresy to go about problem solving in such an unstructured manner. I don't.