smcj wrote:It is clear that the Dharmakaya has no thought processes. Depending on how the Rupakayas are explained that can apply to them too, thus the zombie idea. However rather than zombie/dead-like, enlightened masters are more awake than you or I. So I'm not of that camp.
If you don't like the term "philosophical zombie", fine, but the Jñānālokālaṁkāra makes it perfectly clear that the forms of Tathagatas which appear to sentient beings have no mental constructs. This is not from some sastric interpretation, it's directly from the sutra itself, Buddhavacana. The appearances of the Tathagatas are compared to reflections, sound being produced without a physical instrument etc in the sutra.
Buddhas don't even need to think "I will teach sentient being A Mahayana, I will teach sentient being B Sravakayana". They just teach and different beings perceive their teachings differently.
“It is as follows: Mañjuśrī, here in Jambūdvīpa the rays of the sun only shine at first on the great king of mighty mountains. After that, they shine on the Cakravāḍa and Mahācakravāḍa ranges. After that, they shine on the elevated regions of the earth. After that, they shine on the low-lying regions of the earth here in Jambūdvīpa.
“Yet those sun rays, Mañjuśrī, do not form mental constructs or concepts. They do not think or ponder. The rays of the sun, Mañjuśrī, are free from mentality, mind, and consciousness; they are unborn and unceasing, without characteristics, free from characteristics; [F.285.a] without mental placement, free from mental placement; without elaboration, free from elaboration; without torment, free from torment; not abiding hither, not abiding thither; not high, not low; not bound, not liberated; not knowing, not ignorant; not afflictions, not free from afflictions; not speaking the truth, not speaking falsely; not over there, not here; not on dry land, not in the stream; not the domain of reasoning, not the domain of non-reasoning; neither with form, nor formless. Yet, Mañjuśrī, due to the distinction of higher, middling, and lower places on the earth, the light shines differently, at higher, middling, and lower degrees causing varied shades. 
“In the same way, Mañjuśrī, the Tathāgata, the Arhat, the Perfect and Complete Buddha does not form mental constructs or concepts. He does not think or ponder. Mañjuśrī, the Tathāgata is free from mind, mentality, and consciousness. He is unborn and unceasing. He is without characteristics, free from characteristics; without mental placement, free from mental placement; without elaboration, free from elaboration; without torment, free from torment; not abiding hither, not abiding thither; not high, not low; not bound, not liberated; not knowing, not ignorant; not afflictions, not free from afflictions; not speaking the truth, not speaking falsely; not over there, not here; not on the shore, nor on the non-shore; not on low land, nor on non-low land; not on dry land, nor on non-dry land; not in the stream, nor in the non-stream; not on the plains.
“He is not omniscient, not non-omniscient; [F.285.b] not reasoning, not non-reasoning; not acting, not non-acting; neither behavior nor non-behavior; neither mindful nor unmindful; neither with intention nor free from intention; neither mind nor without mind; neither originated nor unoriginated;25 neither name nor no name; neither form nor no form; neither verbal expression nor non-verbal expression; neither a possible object of imputation, nor not a possible object of imputation; neither visible nor invisible; neither a conducive way nor not a conducive way; neither leading along the way, nor not leading along the way; neither having obtained the result, nor not having obtained the result; neither a concept, nor not a concept; neither free from concepts, nor not free from concepts. 
“Similarly, Mañjuśrī, the rays of awareness from the round sun of the Tathāgata shine brilliantly in the three realms, unimpeded throughout the dharmadhātu with neither edge nor center. Once they shine, they first descend upon the bodies of bodhisattvas, whose aspirations are like the great lord of mountains. After that, they descend upon the bodies of those who set forth on the Vehicle of Pratyekabuddhas. Then they descend upon the bodies of those who have set forth on the Hearers’ Vehicle. After that, they descend upon the body of sentient beings with wholesome aspirations, according to their specific inclinations. After that, the rays of awareness from the round sun of the Tathāgata even descend upon the body of those sentient beings with mental continua that are stuck in what is wrong.26 The rays assist all these beings by producing causes for what will come later, and increase their wholesome dharmas.
“In that respect, Mañjuśrī, the Tathāgata [F.286.a] is everywhere the same, neutral, without concepts, and does not make any distinctions. Moreover, Mañjuśrī, the round sun of the Tathāgata’s awareness does not think, ‘I will teach this person the vast Dharma, but I will not teach that one.’ Neither does it have the concept, ‘This person has vast beliefs, that one has middling beliefs. This one has belief in the Hearers’ Vehicle. This one has wholesome aspirations while that one is low, with wrong aspirations.’ 
“Mañjuśrī, the round sun of the Tathāgata’s awareness does not think, ‘This sentient being has vast beliefs, so I will teach him the Great Vehicle. This one has middling beliefs, so I will teach him the Pratyekabuddha Vehicle. This one has belief in the Hearers’ Vehicle, so I will teach him the Hearers’ Vehicle. I shall come to understand the aspirations of sentient beings with either wholesome or unwholesome aspirations, then purify them and straighten up their view. Even for sentient beings stuck in what is wrong, I shall teach a fitting dharma.’
“The light of the rays of awareness from the round sun of the Tathāgata does not have any such concepts. And why? Because the light of the rays of awareness from the round sun of the Tathāgata has cut off all constructs, concepts, and elaborations. On the other hand, Mañjuśrī, because of variations in sentient beings’ inclinations to wholesome intent, the light of the rays of awareness from the round sun of the Tathāgata is varied too.”  [B.2]
I don't even see how personal or impersonal enters into this. That is a purely Abrahamic concept. Buddhas appear as persons to persons, as devas to devas, to animals as animals, all depending on the karma of the perceiving sentient being. Buddhas themselves are beyond the characteristics of personality (5 skandhas etc).