I have to agree with Tim on all of the above points. In my experience with airplanes, you will never find a soldered wire unless it is properly supported for vibration and all crimped connections are made with a go/no go crimping tool that folds and dents the crimp perfectly each time. These crimping tools will make a consistant shaped crimp using the same amount of pressure each time to ensure the proper amount of "crush" for each crimp. A soldered connection, while useful for circuit boards in electronics, should not be used on wires in a motor vehicle due to vibration induced failures.
This is not correct... Soldering is a superior connection to crimping... the reason why everyone recommends crimping is because soldering takes way too long in for most modern production methods.
The main reason why everyone recommends against soldering is that the solder wicks up the wire and makes the connection prone to vibration failure (or so the theory goes) the only problem is that i have personally seen a solder joint fail from vibration *once*... but i have seen countless crimps fail... even coming off of the $100K tyco crimping machine....
So herein lies the problem... I have the tyco crimper: $500 for the die set and $150 for the frame... If you are going to tell people to crimp because its better then you should qualify that by letting them know that they need a proper crimper... Because if they go and get the $10 crimper from home depot you are doing them a disservice...
Finally, in aerospace where the connection is mission-critical and there is no redundancy, they actually crimp then solder the contact point above the strain-relief with silver bearing solder.