These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: The Art of War
"Funny Aneurysm" Moment: The book was originally written for Helu, the ruler of the Kingdom of Wu. About fifty or so years after Sun Tzu's death, Wu was completely destroyed and absorbed by the Kingdom of Yue.
Additional points when you consider that Helu's son and successor Fu Chai did many things that Sun Tzu (and The Art Of War) would have frowned upon.
Executive Meddling: Not literally, but Sun Tzu acknowledges the dangers that might come if a head of state without military experience or training thinks he's hot shot and decides to meddle with the generals' plans and make the strategic decisions himself. It's why it's important for the general to stand up to the head of state if he immediately sees the flaws in his plans.
Morals, no, but ethics still have a place in warfare. The central assumption behind pretty much the entire work is that the reader will remain in a superior position because of his adherence to these tenets. In real life, almost no one can maintain military and political dominance one hundred percent of the time, and doing things like staging false peace talks and attacking the enemy without declaring war would mean that your enemies would settle for nothing less than your annihilation. What qualifies as "pragmatic" has changed over the years.