Watercraft are far from the only high vibration environment.
Agreed, but marine is the only environment I regularly work in where there is an actual RULE about soldered vs. crimped connections. And the OP's environment doesn't sound like high vibration from the info provided.
What, exactly, about a crimp is going to deteriorate and make it less suitable than solder?
We design and manufacture sensors for the marine industry. As a result, we do a lot of R&D in new and existing boats. I long ago lost count of the number of crimped connections we've found loose, dangling, or otherwise disconnected on existing boats. We're talking many, many, many dozens of such broken crimp connections. Usually one of the two wires wiggles free from the crimp itself, leaving the two ends hanging or (worse) lying on the bottom of the hull, potentially exposed to fluids that accumulate there (including water, fuel, and oil).
I suspect what happens in many cases is that the additional mass of the crimp itself "jerks" down on the wires during normal watercraft operation. We regularly measure 2-3G shocks on the Z axis from the hull hitting chop, and the crimp experiences that over and over during years of operation. This is the mechanical equivalent of someone yanking on the wires, which over time can lead to one of them pulling out of the crimp.
Never once have I seen a "broken" solder connection on a watercraft. I've seen plenty that weren't properly strain relieved, but none that were broken.
My solution in such cases is to discard the crimp, solder and heat shrink the connection, and then mechanically support and strain relieve it. This complies with A-11. AYBC *prefers* crimps but allows properly supported soldered connections, as I quoted above. The result is much more reliable than a crimped connection, IMHO. Granted you could get additional reliability out of a crimp by strain relieving it too, but since the spec doesn't require that nobody does it, with the long-term results as described.
The funny part is that the watercraft owners/operators often say something like "Yeah, that stopped working a long time ago but we never figured out why." These crimps are often buried behind bulkheads where they are not readily inspectable. Such connections should be made as permanent as possible (such as the technique I described above) on the presumption that no one may ever view them again.