Early ITT we had a comment defending McClellan and I was just thinking about him today as I was contemplating the nature of generalship in general.
I've never been able to get into wargaming despite my fascination, and I think a big reason is that I'm always trying to pull some Sun Tzu, Napoleonic, BHL Hart indirect approach move of genius. When the day to day of war is more about competence. Most of the time it just pays to be cautious and competent and by the book.
Way back in the 2000s I played a Civil War PBEM game, and as part of the quiz they asked me what I thought of someone who rereads the rules all the time. And I said he sounds too cautious.
Most of the time it pays to avoid risk. And most blunders come from being over daring.
McClellan 1862 and France 1940 are too examples where the over-cautious approach lead to fiasco.
On the McClellan case, I would say that the bigger problem was that he was too daring strategically. He tried to pull of a MacArthur Inchon-type amphibious flanking maneuver. Be the Little Napoleon. But he just wasn't cut out for that. Splitting his army in 2, seperating himself from his base and capital, was daring, too daring. He could have blitz'd into Richmond, but he wasn't that man.
If he had just done what Lincoln wanted, he could have just slowly crawled his way down from DC to Richmond. It would have been like Grant 1864. Even if he was slow and made mistakes, there wouldn't be the opportunities for Jackson and Lee to keep threatening DC and upend it all.
I guess being too by the book has its problems too. One example would be Old Brains Halleck, who wrote the Jomnian West Point manual on war. After the surprise at Shiloh, he took over from Grant, and made sure to fortify every single night like the Romans. And turned what coulda been a blitz into Corinth into a slow crawl.
I guess caution needs to be balanced with common sense flexibility and risk management which is the opposite of rash wreckless boldness.