Bonus for another adjecent hoplite (+10) appears all the time, not only when there is actually second hoplite nearby. Can't say if it is only tooltip bug and no calculated in fight, or opposite. This bonus is always added to the final seen sum of strength. Also noticed that the little sword icon next to every bonus description is white for + bonuses and red for - bonuses. But for this particular bonus for adj hoplite, the sword is sometimes red, sometimes white without any rule.