No t to mention that a 4 will loose to a mine as well... I think the only certain you have is when a 5 attacks and looses... it was definitely a mine in that case...
But I agree with Kevin: it's fine the way it is. This is a strategy and memory game after all, so "automatic revealings" would take some fun out of it...
(Cacher) Si vous attendez que ce soit à vous de jouer, cliquez sur "changer" à côté du "rafraîchissement" sur la page principale, puis réglez le rafraîchissement de la page sur 30 secondes pour que votre tour de jouer apparaisse pplus vite. (Servant) (Montrer toutes les astuces)