In a recent post on Harvard Business Review bloggers network, we discuss the extreme focus business model of Germany’s famed Mittlestand: Quick test: name one company that does one thing and does it very well. The companies that occupy the limelight are typically diversified giants that achieve growth through constant expansion into new markets and the introduction of additional product lines (just think P&G, GE, and Microsoft). But the truth is that the really successful companies are highly focused, achieving unprecedented efficiencies by designing a business model with a razor-thin focus and learning to do the one thing really well. Many of us academics still teach an old case about Shouldice Hospital, which only treats simple cases of hernias and nothing else but does it…