Actually, the general consensus seems to be that it will be revealed 'after' death, not even 'at the time of death'. At death, all you have to do is remember Krsna's name and you'll go to Goloka.
A devotee told me recently that during one class, the speaker said something to the effect that it was going to be exciting to die and wake up in Vrndavana and finally find out who we are - either a desire tree or cow or gopi. !!! I have no idea where this insane notion came from. It's certainly not in sastra or Srila Prabhupada's books or the acaryas' books.
Srila Prabhupada makes it very clear in Teachings of Lord Caitanya, (page 318) what state of realization one must be in at the time of death to be qualified to enter Vraja lila:
As stated in the Bhagavad-gītā, a materially contaminated person transmigrates to another material body by material consciousness. At the time of death he thinks materially and is therefore transferred to another material body.
Similarly, one who at the time of death *is situated in his pure spiritual identity* thinks of the spiritual loving service rendered to the Supreme Lord and is transferred to the spiritual kingdom, to enter into the association of Kṛṣṇa.
In other words, *the qualification for being transferred to the spiritual kingdom at the time of death is to think, in one’s spiritual identity*, of Kṛṣṇa and His associates. No one can contemplate the activities of the spiritual kingdom without being situated in his pure, spiritual identity (siddha-deha).
Yes, those verses from BG are always interpreted in the wrong way as you indicated. When Krsna says "remembering Me alone" it indicates complete absorption in your relationship, which is not possible if one still has anarthas, ie: material consciousness, and that directly relates to the next verse re "state of being" or consciousness.
Once you have actually realized your eternal identity, ie: the stage of bhava, you are on the transcendental platform and only serious aparadha could cause you to fall from that platform. At that stage you don't have to endeavor to stay focused anymore, ie: you are no longer 'practicing' because you have reached the goal, ie: the preliminary stage of prema.
Srila Prabhupada confirms this in a morning walk conversation Nairobi, 11.2.75:
Harikeśa: I'm curious about the destination of a neophyte devotee. If a neophyte devotee is with determination endeavoring for purification but he were to meet with death as he is still influenced by the lower modes, although he is seriously trying, then does he take another birth or does he go to Kṛṣṇa?
Prabhupāda: No, he has to take another birth. If he is not completely purified, he has to suffer another birth. Nobody is allowed to enter into the spiritual unless he is cent percent pure. No allowance.
Then he has to... Therefore it is said, śucīnāṁ śrīmatāṁ gehe yoga-bhraṣṭo sañjāyate [Bg. 6.41]. He is given chance, another chance, to take birth in a very pure brāhmaṇa family or rich family so that he may take again the chance, not in, he is allowed to enter. He is given a good chance again. That is his benefit.
Even if you are failure, still, your next birth as a very first-class human being is guaranteed. Not for others. It is only for the yogis. If he is... Therefore it is said that "What is the loss even if he is failure?" Tyaktvā sva-dharmaṁ caraṇāmbujaṁ harer bhajann apakvo 'tha patet tato yadi yatra kva va abhadram abhūd amuṣya kim [SB 1.5.17].
This verse is very important. Even by sentiment one comes to Kṛṣṇa consciousness and discharges the regulative duties, chants Hare Kṛṣṇa, his next life is guaranteed as a human being. Even he does it for some time—he is not perfect—still, his next life is guaranteed. But others, there is no such guarantee. Even if he discharges his so-called duties, material duties, there is no guarantee that he'll become a human being. [break]
Harikeśa: They let him (Ajamila) stay in that body and then he went to Hṛṣīkeśa and performed devotional service and then became perfect.
Prabhupāda: No, he was already perfect, but to increase his desire—"How shall I go Vaikuṇṭha?"—another time he had to go. He was a perfect; otherwise how he was saved from the Yamadutas?
Harikeśa: So if a devotee dies and remembers Kṛṣṇa, although he is not perfect...
Prabhupāda: Unless he is perfect, he cannot remember Kṛṣṇa. That is not possible. That is not possible. That is theory only. He must be perfect. Somehow or other, he has fallen, so Kṛṣṇa gives him the chance. That is special concession for devotee. Some way or other, you become devotee. Even if you cannot finish the whole job, if you fall down, still, there is guarantee that you get your birth in a very good society. That is the prerogative."
Here is further confirmation that one must be fully conscious of one's desired relationship with Krsna at the time of death in order to qualify for entrance into bhauma-lila. From Teachings of Lord Caitanya, page 318:
The process of transcendental realization is to follow in the footsteps of the associates of the Supreme Lord; therefore to think oneself a direct associate of the Supreme Lord is condemned (ahangrahopasana). According to authorized Vaiṣṇava principles, one should follow a particular devotee and not think of himself as Kṛṣṇa’s associate.
In this way Rāmānanda Rāya explained that one should accept the mood of the damsels of Vraja. In the Caitanya-caritāmṛta it is clearly said that one should accept the emotional activities of the associates of Kṛṣṇa, not imitate their dress. One should also always meditate upon the dealings between Rādhā and Kṛṣṇa in the transcendental world.
One should think of Rādhā and Kṛṣṇa twenty-four hours a day and engage in Their service within one’s mind, not externally change one’s dress. By adopting the mood of the associates and friends of Rādhārāṇī and following in their footsteps, one can ultimately achieve the perfectional stage of being transferred to Goloka Vṛndāvana, the transcendental abode of Kṛṣṇa.
By adopting this emotional mood of following in the footsteps of the gopīs, one attains his siddha-deha. This word indicates the pure spiritual body, which is beyond the senses, mind and intelligence. The siddha-deha is the purified soul who is just suitable to serve the Supreme Lord. No one can serve the Supreme Lord as His associate without being situated in his perfectly pure spiritual identity. That identity is completely free from all material contamination.
As stated in the Bhagavad-gītā, a materially contaminated person transmigrates to another material body by material consciousness. At the time of death he thinks materially and is therefore transferred to another material body. Similarly, one who at the time of death is situated in his pure spiritual identity thinks of the spiritual loving service rendered to the Supreme Lord and is transferred to the spiritual kingdom, to enter into the association of Kṛṣṇa.
In other words, the qualification for being transferred to the spiritual kingdom at the time of death is to think, in one’s spiritual identity, of Kṛṣṇa and His associates. No one can contemplate the activities of the spiritual kingdom without being situated in his pure, spiritual identity (siddha-deha).
Thus Rāmānanda Rāya said that without attaining one’s siddha-deha one can neither become an associate of the damsels of Vraja nor render service directly to the Personality of Godhead, Kṛṣṇa, and His eternal consort, Rādhārāṇī. In this regard, Rāmānanda quoted a nice verse from Śrīmad-Bhāgavatam (10.47.60):
“Neither the goddess of fortune, Lakṣmī, nor the damsels of the heavenly kingdom can attain the facilities of the damsels of Vrajabhūmi – and what to speak of others?”
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"He said that it was nonsense to think that we have to realize our eternal identity before going back to Godhead. That all that is necessary is to be completely free from material attachments and to be concentrating on Krishna. That's it."
The nature of existence is that we are attached. Right now we are attached to the material world, and that's all we know since eternity. To get out of here, we need to attach ourselves to something else. What? Impersonal liberation is to not be attached to the material world, but not being attached to anything else. If we are attached to God in general, we can attain shanta rasa. That is what we get if we are attached to God Krishna, without being attached to his pastimes and service.
To be able to take an active part in Krishna's pastimes, we need an identity. Of course, unless we aim for a birth like a straw of grass or a tree in Krishna's pastimes.
So we need to ecquire an eternal identity, somehow, to be able to enter Krishna's eternal pastimes.