Okay, now I understand what we are talking about but I still don't find it remarkable in any way. I can come up with an endless number of similar processes. For example the FTP clock. I have a public FTP server and at some point in time I create a directory named 1. Then I open that directory and create a subdirectory named 2. Then 3 another level deeper. And 4. And... I don't see what is special about such a process.
Also note that this is not precise in any meaningful sense, neither in the case of Bitcoin nor in the case of my FTP clock, we are just labeling random points in time with names like »the point in time I found block 12345.« or »the point in time I created the subdirectory 42«. I could throw a plate against a wall at label that as »the point in time that plate hit the wall«.
This labeling does not establish any regular interval, it does not help identifying what this point in time was or what else happened at this point in time. It's a trivial tautology, every event happens at exactly the point in time it happens. And every clock is as precise - in your sense - as Bitcoin, the exact point in time this clocked switched from 11:59:59 to 12:00:00 is not different at all from the exact point in time you minded block 12345.
Maybe that clock was actually 5 minutes fast and it was really only 11:55:00 but that is inconsequential for the way you use »price«, every tick of that clock still labels a precise point in time. But an actual good clock is useful because it assigns labels like »2018-04-18 19:49:17« at regular intervals with some precision depending on the nature of the clock. Bitcoin, the FTP clock, and the plate hitting the wall are useless in that sense because the relation between points in time and the assigned label are to a large extend random. You could use Bitcoin as a crude clock with an time resolution of about ten minutes but that is not a good clock.
Finally note that the Bitcoin clock does not even really tick at the point in time you mined a block because that block might get orphaned or simply rejected for whatever reasons. Only in hindsight can you say that it ticked when this or that block was mined, once there are enough blocks on top of it that it becomes reasonably unlikely that another chain might become the longest one.
Wait, finally finally. What is the point in time you mined block 12345 exactly? There are zillions of subatomic particles moving around in you mining hardware, how would you ever be able to pin down precisely when you mined a block? Did you mine it now or do you have to wait until this electron over there also passes through that transistor here and increase the charge on the capacitor to the left another tiny bit? When you really think about it, the point in time you mined block 12345 becomes quite a fuzzy concept at the microscale. And so even before you start thinking about the uncertainty principle or relativity.
