Let's round up this wheel truing story:
There are tons of articles in the mags and load of videos on YouTube on this topic. In fact I got pretty confused in the beginning, but in the end I could boil it down to one useable article (in the british "Classic Bike" mag) and one really good down-to-earth video on Youtube.
The take aways from from the mag and the video:
1. When the wheel is in your truing-stand in mounted in the forks, you start tighten the spokes, always do one complete round. You can start at where the hole for the valve is.
2. In the beginning, tighten every spoke an equal amount - like 1/4 of a turn. (IMPORTANT)
3. After each pass, take a look at your pointer or gauge.
4. Some tighten each and every spoke when they do a round / pass, Others only tighten every 4. spoke in one pass, and then move on to next set of four's. Some might think it gives you to much to keep track of. personal choise
5. When you start truing, start with taking out any radial slack first. When done continue to the sideways slack (most videos tend to forget mentioning this, and some only shows how to correct for sideways slack.
I found this video very useful: https://www.youtube.com/watch?v=4seylmsPzAk
I'm not related to the guy / company in any way 
The guy in the video has got a own-to-earth approach, and he makes a point out of saying, that it is important that all spokes has equal tension.
With your spoke wrench, tap 2-3 times on each spoke as you make a pass. From the sound you can easily hear if some spoke has less tension than others. Tighten these as you encounter them.
As I mentioned earlier, and also mentioned in the video, it's not easy to get a 40-50 years old rim running completely straight.
Of course if you start out with brand new repro rims, it's another game.
A good way of stressing yourself:
... using 2 dial-gauges at the same time!
Start with one, or better just a pointer. Gradually as your rims gets more a more true, you can swith to a dial-gauge, if you wish.
When your spokes are almost as tight as you like them - like 85% or so grab a punch and a small hammer, and hit each and every spoke, like this:
There a some motion blur on the hammer head, but you should be able to get an idea of its size, a small hammer will do nicely. The effect of doing this is, that the blow will move the head of the spoke a tiny little bit inwards, again making the spoke a little looser. When you have punched all spokes, make another last pass and tighten every spoke.
This trick will maintain the tension on the spoke for longer, making you do without an additional tightening after say 500 miles (hopefully)
VERY important: When finished tightening all spokes, any surplus thread which protudes out of the nipple, must be cut /grinded away, or you will inevitably have a puncture.
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and besides, you can't tell when looking from the outside.
let's see if anyone still follows this thread... 
more than 20 bits if you include 5 screws and 2 paper thin gaskets. A far cry from modern electronics, as everything can be taken apart and reassembled.
