Specialization bug?

[Norok]

X-Posted to Bugs because I do not yet know if it is one. I will pose my question here too.

I am unfamiliar with the exact benefit of spell specialization so perhaps this is working as intended:

On my druid I leveled up specialized in Evocation. I saw that being specialized in this gave me a marginal increase in spell damage.

On my cleric I am specialized in Alteration. I see a marginal increase in healing done per spell.

On my druid I respecialized to Alteration. I am at around 140's maxing it but my healing spells do not do more healing and it seems that the spell damage increase from Evocation spells is still in effect. Is this working as intended or a bug?