I show your post about the synthetic apperture radar interferogram in L'Aquila earthquake where you state: "I'm pretty sure this data shows the Earth growing. However they only provide two numbers (2.8 centimeters and 25 centimeters) and no vectors. Movement, but to where? It would be interesting if they told us what the interferogram data shows:"
Well, if you look carefully in the Science Daily post, which reads: "Each fringe of the interferogram, corresponding to a colour cycle, is equivalent to an Earth surface displacement of 2.8 cm along the satellite direction (the bold letters is by S.T.)." it is clear that this is vertical movement, i.e., uplift.
Now, since there are ~9 fringes, and each fringe represents 2.8 cm along the satellite direction, the total displacement-uplift at the center of a ~26 km by ~13 km dome is ~25 cm, which corresponds to a volume of ~3.3x10^7 m^3 or ~10^11 kg of Excess Mass. So here is your measured earth growth; and this is not theory. It is hard-core modern technology data.
This earthquake or volcano related doming-uplift, the size of which depends on the earthquake magnitude or volcano size, has been observed before, e.g., Izmit earthquake and Mount St Helens volcano.
As for the prediction of the L'Aquila earthquake be a bit cautious. The problem of earthquake prediction is not solved yet. Especially mainsteamers with their plate tectonics, elastic rebound, and static stress myths have a real problem understanding the physics of the earthquake source. This is why it is almost unanimously recognized that the physics of the earthquake source is not known. It follows that it is impossible to deterministically predict a phenomenon when you do not know the cause and effect relationships that govern the phenomenon itself.
Although there are various precursors, among which the increase in radon content, since an earthquake is a quantized phenomenon you never now if and when the necessary quantum-limit will be reached. It might never be reached or it might be reached within seconds. Then even if we have a swarm of small earthquakes, like in L'Aquila, in the 99% of the cases this is not followed by a much stronger earthquake. The real problem with L'Aquila and other earthquake hit areas is the quality of structures, and earthquake preparedness in general, and of course the reasons if they are not good.