I’ve added/removed gear with ONLY attunement, and even closed/opened the character screen to refresh it after every swap, as a paladin, to see ‘healing effectiveness’ stay exactly the same.
Also related: if you use Judgements ‘Pious offering’ node, using more MP gives you more consecrated ground damage. However, the MP that comes from putting attunement on gear gives NO dmg increase to consecrated ground. (probably judgement too, but i only use consecrated ground).
yes i’ve tested extensively, going from no gear → only attunement gear.