The [excellent] British TV series “Sharpe” touches on this topic. The British Army ended up with some really incompetent commanders as a result.
https://en.wikipedia.org/wiki/Sharpe_(TV_series)
I did catch most of Sharpe. Good stuff. Col. Henry Simmerson was the perfect example of an aristocratic and incompetent British officer. Here he is being chastised by the Duke of Wellington. Great scene.
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