Aeroelectric method
I suspect that the SteinAir method is actually the Aeroelectric (Bob Nuckolls) method. He just didn't post a youtube video. What Stein's video doesn't show is that you can 'stagger' the pins by clipping each mating pair longer/shorter than its neighbor(s). When you do that, you can keep the overall joint diameter almost as small as the wire itself, and it will 'key' each mating pair by length.
To answer maus92's question, current capacity is measured by capacity per pin; not the number of pins. The machined pins are rated at around 7 amps each. Most of us limit them to around 5A each, but you can use multiple pins for higher current. The technique is to use 20 awg 'ballast' wires ~12" long on each pin, and collect them into a splice with the main (heavier) conductor. The ballast wires provide a method to terminate into the small barrel of the pin, and help balance distribution of the current among the common pins.
Note that for something like trim motors, it's not amp ratings that is likely to bite you. There's almost no power carried there (it will run off a 9V transistor radio battery), and most of the wires just carry 'signal'. At those low levels, joint resistance is the big enemy, and molex style connectors are not gold plated. The Dsub pins are gold plated, and tend to be much more reliable in less than ideal environments.
All the above is covered in the Aeroelectric Connection book, and on the Matronics list.
edit: As mentioned, there's wide variation in opinion about this style pin. It's worth pointing out that the primary reason mfgrs moved from soldered joints to crimped joints was not joint reliability of a properly soldered joint, or stress risers in soldered joints (crimped terminals have them, too). The reason was two-fold: it's faster to train a line worker to squeeze a ratcheting crimper until it releases than to train him in how to make a reliable solder joint, and it's faster during production runs to crimp a joint using a pre-insulated terminal than it is to solder and then insulate/strain relief. The reason I mention this is that, as stated here, many have problems making up these miniature molex style connectors properly, but few have problems with Dsub pins, which they must master for the rest of their avionics anyway. Why not go the the known-reliable components *and* techniques?
Charlie