In my work running a company, I love looking at financial documents and balance sheets to discover the ratios between assets and liabilities and figure out an organizations solvency. If you have never seen a balance sheet before - take a look at this tutorial I filmed for the Washington Non-Profits association.
The key take-away is that a balance sheet is a snapshot in time, it is a report of the financial status of the organization at that specific moment.
The same is true with teaching case studies - they are snapshots of what was true at that moment in time. They represent the moment when that event happened, and it may never happen that way again. Many people use case studies as a tool to say 'what would YOU have done?' There is merit in that line of reasoning, however impossible it may be. Since you were not there, and you don't have the same attachment, emotional investment and engagement with the process, it is hard to say what you really would have done.
When I teach workshops I stress the importance of focussing on the differences in a situation, rather than what is similar. Focussing on what is similar can lead me to say 'this is the same as last week...' and place a solution in play that may or may not have relevance. Our brains are wired to search for patterns, so the default for our brains is to say the situations are the same, when in fact they are probably very different.
By focussing on what is different, you can make sure you are staying in this moment, and not reacting to the past. You can stay active to the people, processes and engagement at hand, rather than dismissing new information that can be the key to innovation.
So remember - when you see a situation that seems the same - ask yourself if this resembles a snapshot in time you had previously, and focus on what is different to stay active in the moment.
Solutions you used yesterday are often not the correct solutions for today.