I've been doing some spring cleaning which has included a knitting magazine reorganization. I started flipping through a few of the oldest ones including the premier issue of Vogue Knitting Fall/Winter 1982.
I ended up reading an article on gauge swatches and things have really changed a lot since it was written. The article is uncredited but the designs on the editorial pages do credit the designers. I did find this a little odd but standards change over time.
The article states that gauge is not measured in half stitches but it does not explain why. It has the swatch cast on as an exact multiple of the stitches required for 4 inches wide of knitting. The gauge is measured over 1 inch in the center of the swatch for both rows and stitches. The unnamed writer also recommends pulling the yarn tighter as you knit if you are having trouble getting stitch gauge but are getting row gauge. (I'm not sure I could maintain that knitting style change throughout an entire project). There is absolutely no mention of blocking the swatch. One of the reasons I ended up designing all of my own garments was my inability to get gauge. I think I now understand why that was happening.
I currently knit much larger swatches, that are carefully blocked. I measure more than once in different spots on the swatch, over more than 4 inches and I average the results. I do an outline of the swatch on graph paper before blocking to compare to post blocking results to check for shrinkage changes in either width or length. I recheck gauge on the garment back after knitting about 6 inches if blocking did not create any gauge changes. If the fiber I'm working with lacks elasticity I also hang the swatch and recheck for stretching after 24 - 28 hours.
It is interesting that such a basic part of knitting instruction has changed so much in 29 years.