From the several warmonger-focused games I've played, I think it is. This promotion favors the attacker, because you can "save" it for key moments when your units are at 1-3 HP, instead of pulling back to heal and slow down the offensive. Too many times I just popped the promotion on my turn and finished off a damaged enemy unit that just dealt -7 to me the previous turn in closely contested combat.
IMO this promotion should be removed altogether in favor of healing a smaller percentage of total HP upon any other promotion, like in Civ 4. Alternatives to getting rid of it completely are:
1.) limiting its use to friendly or neutral territory (to simulate supply routes - it's harder to reinforce in enemy territory)
2.) reduce the HP healed when near enemy units (this was used in Panzer General - units would only reinforce to 8/10 instead of 10/10 when enemy units were next to them)
IMO this promotion should be removed altogether in favor of healing a smaller percentage of total HP upon any other promotion, like in Civ 4. Alternatives to getting rid of it completely are:
1.) limiting its use to friendly or neutral territory (to simulate supply routes - it's harder to reinforce in enemy territory)
2.) reduce the HP healed when near enemy units (this was used in Panzer General - units would only reinforce to 8/10 instead of 10/10 when enemy units were next to them)