yes, that’s exactly what annoyed me – that the hero deals damage to his own troops. That’s why I can use a weaker ability of the leaders, but more often I go for the Executioners, and therefore the actual percentage of games in which I use it is not high. Besides, it can be justified in hero battles, but creeps are easily defeated anyway, so essentially it’s still rarely used.

P.S. It’s enough to compare the HP of Warmongers and Soldiers, and it will immediately become clear why the former are the obvious choice. And their rage doesn’t save them from a couple of Stone Skins and Lightning spells. If their attack was guaranteed, they would be more valuable.