Let’s see. I have 650 men. The enemy has 1,500 (although Custer may not have known this).
My plan to deal with being outnumbered more than 2/1 is to split my men into three roughly equal-sized groups, inviting defeat in detail.
Sounds like an excellent plan to me.
Front and flank attack, movement, offensive, surprise.
That’s the way to attack a force in the cavalry, and that’s what Custer did. As US general in chief Nelson Miles and Confederate cavalry general Rosser said, the plan was good.
The front columns didn’t do their job, and the flank column, with Custer, was left alone.
Chancellorsville, Brice’s Crossroads.
He went to the well once too often. And, he divided his force, had subordinates whom he mistreated and still expected to be loyal to him.
Custer was a fool, and good men died for his foolishness.