Pleasanton's reputation has not fared well, but one of his great services to the cause was to promote three young officers -- Custer, Elon Farnsworth and Wesley Merritt -- to brigade command. They were chosen quite specifically for their aggressiveness, the idea being to get out and smoke Jeb Stuart. Farnworth was killed at Gettysburg (at age 25), but Custer and Merritt emerged, along with Tom Devin, as a highly competent command trio that in 1863-64 slowly wrested cavalry dominance away from the confederates. John Buford might well have figured prominently in this command evolution as his star had steadily risen, but he fell ill and died in the winter of 1863. It's a small world department: one of Buford's aides at the time of his death, and present at the bedside, was Myles Keough, who would die with Custer at the Little Bighorn. Devin was one of Buford's brigade commanders at Gettysburg.