Well, for now, I've heavily invested in Blood magic. I'll follow this path and then, for comparison, I'll level up in Tears... But in the thread you mentioned, there's more theory than practice... by the time you cast everything that's mentioned there, your troops will be destroyed. The game starts immediately, and you need to destroy the enemy right away; whoever does it first wins. And while you're summoning elementals, giving Stone Skin, etc., your troops will be killed. Besides, I believe that each battle is unique, and you can't set a rule for how to fight! For example, in Heroes 5, when playing duels with small armies, the most important thing is which hero goes first. If it's a mage, they can cast Meteor Shower, and in 50% of cases, with incorrect troop placement, the game ends! Perhaps Sacrifice is effective in long battles, but in the average scenario, all battles last 2-3 turns, or even less.