"And I, Ānanda, will not proceed with you
as does a potter with an unbaked (vessel), not fully dry. I will speak, Ānanda, constantly reproving, constantly cleansing"
Apologies for allowing my frustration with the English of your question and your remark to show itself in the tone. But you should overlook tone and focus on whether or not what was said was well-said or not.
I completely understand how it can be that you do not understand what is difficult to understand about your question. Your clarification does not help. But I will give it another shot.
I did not, in answering your question, and in responding to your comment, intend to emphasize your misunderstandings, but to point them out was necessary in order to correct them.
You apparently have a misconception concerning the nature of the middle way. That is clear because there is no way a person who understood the middle way could think that it could possibly, in any way, apply to innanimate matter. You are either inventing the meaning of the term yourself or you have followed the invention of someone else that does not understand. That misunderstanding should have been cleared up reading the definition in the link I supplied. The link leads to several different interpretations by different translators, you can take your pick.
The Middle Way is describing an attitude to take with regard to taking action.
It is an instruction to not take even one step either towards self-indulgence or self-torture. That is the Middle Way.
It does not involve any sort of state or movement between annihilationism or eternalism.
It, itself, is not a point of view between annihilaationism and eternalism.
In so far as the Middle Way is defined as The Four Truths, it is a point of view. But it is one that avoids the issue of existence and non-existence, thus:
Whether or not there is no self and death is the end or that there is an eternal soul, there is dukkha (pain, ugly-uk-ukky-k-kha), and the Middle Way is the way to the end of that dukkha.
It is a way to interact with kamma such as to bring kamma to an end.
Folowing the Middle Way, one avoids the consequences of acting from the points of view of annihilationism or eternalism.
Example: You can only get a date with the most beautiful lass in the land if you lie. So considering the Middle Way, looking in the Magga under Sammā Vaca, Consummate Speech, you see that lies are to be avoided. You abstain from that lie. You have just followed the Middle Way.
What did you do? Nothing. Where are you between annihilationism and eternalism? Not between! If you must characterize it by location, it is 'apart from'. You didn't go anywhere. You intentionally 'not-did'. The result is not something somewhere, it is the ending of the kammic stream which presented itself to you in the form of the pleasant sensations at the eye of the most beautiful lass in the land and the thirst for her that resulted.
You evaluate the results. The result is a negative. You will not, because of that intentional not-doing, ever experience having to live with an old hag that has lost her beauty, doesn't put out and does nothing but eat, spend money and argue with you in the old age which you can now enjoy in peace.
So next time you will have less difficulty abstaining, walking the Middle Way, in a similar situation.
That explains the meaning of The Middle Way.
Now please explain how a rock could fit into this picture? Somewhere in your thinking you have constructed the Middle Way into both a point of view and an actual state between annihilationism and eternalism... one in which a rock could be found. Not so!