Is the fact that the Lorentz contraction cannot be proven the real weak spot of special relativity?

The Lorentz contraction is probably the most used equation in physics today, the square root of one minus v squared over c squared, and it was the equation Lorentz and Einstein used to say how much a moving object shortens in the direction of motion. It was introduced to answer the Michelson-Morley experiment, which indicated the earth was not moving: rather than accept a motionless earth, they said the measuring instrument itself shrank just enough to give a false negative, and then had to dilate time to match, which is where the whole edifice of relative space and time comes from. On this view even the earth, thought to orbit the sun at thirty kilometers per second, would have to shrink about three inches to make the numbers work. But here is the dilemma: you cannot prove it. If there are no absolutes, there is nothing fixed from which to measure whether the earth or a six-inch rod actually contracted, so length contraction can never be verified; it is simply a theory adopted to avoid answering Michelson-Morley squarely. That is the price they pay for refusing to accept that the earth is motionless: they end up with nothing absolute from which to measure anything, which is a mass of confusion. So yes, the unprovability of the contraction is the real soft spot of the theory.