[VadeRetro]

The precession of Mercury's perihelion was a success for relativity, but that success lay in explaining a known and puzzling phenomenon, not in predicting it.

[longshadow]

The precession of Mercury's perihelion was a success for relativity, but that success lay in explaining a known and puzzling phenomenon, not in predicting it.

Exactly; that's why the starlight bending observation during the solar eclipse was so important; it represented a prediction made by ahead of time by GR for a phenomona that had not previously been observed or predicted. And he nailed it. It was a "Full Monty" falsification test of GR.