Look at it like this. In the common thinking about this game, A card is usually qualified in three ways: "Bad": A card that actively harms you, provides no benefit to you, or an easily countered benefit to you. (Majordomo, Magma Rager, a lot of cards with high mana cost that are simply unplayable given current meta and tempo) "Good": A card that provides a benefit to you (Senjin Shieldmasta, Frostbolt), and "Great" A card that provides 2 unique benefits to you. (Dr. Boom, Defender of Argus, Abusive Sergeant.)
This card, for 4 mana, a very reasonable costs, gives you 4 unique benefits. Not only can you utilize the card to attack twice, it also heals you twice. 2 health doesn't seem like a lot, but it's actually exceptional. It assures anything you hit with two attack or less is no net loss to your health, anything you hit with 3, 4, or 5 attack gives you a nominal loss, and that anything you hit between say 6-8 attack does damage to you, but a "normal" amount of damage you'd expect attacking a creature.
The card's only counters are Harrison (a utility legendary that is a counter, but not a brutal counter, you could literally play your other Truesilver to take care of it) and Acidic Ooze, both of which, given the mana which you can play this card for, will speak for a majority of the mana of your opponent's next turn. Plus, he can't play them on your turn. You've already gotten your 2 unique benefits out of this card if you attack the turn you play it.