The next methodological note is as follows: If the Einstein method is used for synchronization, the notion of time becomes limited. First, only one of two independent variables - spatial coordinates or time - remains independent, whereas the other is associated with the state of motion (subjectivism) and properties of light speed (but why is it not associated, for example, with the speed of sound or with the velocity of Earth, etc.?). Second, since the independent determination of spatial coordinates and time is required for determination of velocity, light speed itself becomes indeterminate quantity (immeasurable, postulated).
As relativists like to potter with idle inventions! One of such the "Great" idle inventions of the relativity theory is a light clock (for 100 years anybody did not try to construct a pre-production model at all and will never try to make it!). And it is not because that it is impossible to create ideally flat, ideally parallel, ideally reflecting mirrors. That is why that we cannot observe "TICK-TOCK" sideways as it is described by the SRT. Such a clock "works" to first "TICK" and ceases to be "identical", as a photon at the moment of "TICK" registration should finally be reacted. Nevertheless, we will return "to ours relativists", which often use a "light clock" for demonstrating the time slowing effect  (Fig. 1.10).
However, in exactly the same manner we can also consider a periodically reflecting particle (or a sound wave) at speed and obtain the arbitrary time slow-down . It is known, that the orthogonal velocity components can be described independently: the horizontal motion at velocity relative to an instrument will in no way influence the vertical oscillations of a particle moving at former velocity . The question on experimental verifications of the postulate of light speed constancy will be analyzed in Chapter 3.
The time slowdown in SRT is nothing else, but the apparent effect. Remind that for a sound the duration of a hooting of trumpet also depends on the velocity of a receiver relative to a source (a trumpet), but nobody makes the conclusions on time slowdown from this fact. The fact is that observer's "decision" to move at any velocity is in no way bound causally with sound emitting processes (as well as with other processes in a trumpet). Let a singer be continuously singing a song in the resting atmosphere, and his twin brother be moving away from a singer at about the speed of sound : , and then he will move toward a singer (with the same ratio ). Though the song will be distorted, nobody had yet recorded more rapid aging of a singer. Let now we modulate with the same song the light in pursuit of the twin brother, who departed on a rocket at about the speed of light, but with the same numerical value . Now the twin brother will listen the same distorted song. Why the situation must change in this case, and the "home seating" brother must grow old? And, if some living organism will be characterized by some certain radiation frequency, that distinguishes him from the dead organism, then, really, because of your motion (because of the Doppler effect) you will first certify the death of an organism, and then his resurrection? Or it is necessary to postulate the change of objective characteristics of an object, which is not bound with you causally?
Now we make some comments concerning Einstein's time synchronization method. The transitivity of time synchronization by Einstein's method takes place for the trivial case of three mutually resting points. If, however, the points (not lying on the same straight line) belong to the systems moving relative to each other in different (not parallel) directions, then the synchronization procedure can become uncertain: for what time instant the watch can be considered to be synchronized? For the beginning of the procedure, for its termination or for an intermediate instant? Even for the points lying on the same straight line Einstein's method rests upon a completely unverified (experimentally) concept of equality of the speed of light in one and in a directly opposite direction. Actually, the synchronization occurs to be either a half-done calculation procedure, or a multi-iterative process, because the synchronization is performed for two selected points only. These deficiencies are absent in the method of synchronization with a remote source disposed at a middle perpendicular . It allows one to synchronize the time experimentally (rather than computationally), without attracting additional hypotheses, to a prescribed accuracy throughout the given segment (even on a flat section) at once.
Now we proceed to the time measurement units. Certainly, for a separate phenomenon within the framework of some mathematical model any customary quantity can be described in various measurement units and in various scales (both uniform and non-uniform, for example, in the logarithmic scale). This is basically determined both by the convenience of description for the given model, and, as in the case of generalization, by the possibility of using the same quantities for the other physical phenomena and mathematical models (the matching of various fields of physics). However, Taylor and Wheeler's  sarcasm concerning the "sacred units" is completely inadequate. Certainly, we can introduce the factor for converting the time into meters. But this factor is not obliged to be the speed of light: for example, it can be the velocity of a pedestrian. Both aforementioned velocities have, quite equally, no relation to acoustic, thermal phenomena, to hydrodynamics and to many other fields of physics. It is possible to express, generally, all quantities (such as mass, charge, etc.) in meters. However, all these "various meters":
1) can not be summed up,
2) are not interchangeable,
3) very rarely appear in some joint combinations and
4) the same combination is unsuitable for various phenomena.
(For example, the interval has relation only to the law of light propagation in vacuum.) All quantities can be made pure numbers (and we must separately look after all these physical values). But in any case physics will not become mathematics. Physics does not study all illusory combinatorial "worlds" of equations, but only that rather small amount of them, which is realized in the nature (the basic problems of physics are: what interrelations are realized in the nature, why and what are the consequences of this).