Einstein defined the mid time of the round trip time (of light on the trip from A to B) to be the B-time (et vice versa).

Why did the audience believe that Einstein were able to define the half of some period that had not ended before?

To understand this pretence of knowledge use this analogy: Why do humans not define the midpoint of their life time (and celebrate it gracefully)?

You will know the midpoint only after knowing the end point (and the starting point as well). There is given monotonicity between the events "A is sending" < "B is reflecting" < "A is receiving".

We have to inspect two cases only:

1. The repeated measure of Einsteins round trip time would give the same value. In this case A and B did keep their distances, i.e. A and B were at rest with respect to each other, hence A and B share the same frame. But within the same frame there is "Eigenzeit" the only valid time and (a) "A-time" and "B-time" must be the same object and (b) both use the same unique time reference and (c) both must show the same time value simultaneously as all clocks show it in the same frame.

Hence “Einstein's technique of synchronization" is in misapplied if the half of the round trip matches the half of the round trip again and if there is no guarantee added that t[AB]=t[BA], i.e. that A and B are at absolute rest!

Note: If reliability is given the technique creates wrong positive results. If A and B are moving with v!=0 the one-way times are different. Hence the Eigenzeit (as duration) signaled from A to B differs from the Eigenzeit (as duration) sent from B to A.

2. The repeated measure gives a different value: In this case the previously signaled mid point of time was the wrong one and "B-time" was given a value by random. As (a) there is no possibility to avoid this defect (proved by your life span) and (b) any correction might be fixed afterwards only but (c) the fixes cannot change the previously deployed readings there will no feasibility at all and forever.

Note: If the value signaled does not match again the technique is infeasible anyway.

Finally, hopefully you can see that the idea to define time was debunked. But the main stream still dreams on.

Why?