I’m in agreement with you on this. Being from a Southern state I was basically taught that Northern generals were butchers and that the only reason they won was because of superior men and resources. Well, along the way I read J.F.C. Fuller’s book Grant and Lee. He pretty well destroyed that silly argument. Ditto, Horace Porter’s Campaigning With Grant. Fact is, Grant is simply one of the greatest Captains ever. He was without guile or pretense, odd for a military man. There was nothing of the martinet in him. By all means, if you haven’t read it pick up his Memoirs, one of the greatest ever written. Shelby Foote was an unrepentent Southerner and he loved Grant. That speaks volumes.
Grant knew that in a stand up fight he could not compete with the Southern frame of mind and leadership in battle. Cold Harbor was indicative of that. He kept attacking so the South would break, which it never did, and made him realize he could only win by continuing to bleed off manpower. He had the logistics and men to throw in, the South was running out.