I was curious, so I did a little research, and here's what I came up with regarding miniature overshot. First, an internet search turned up the names of two weavers from the earlier half of last century who made designs in miniature overshot. Josephine Estes worked on miniaturizing large overshot drafts in the 1930s. Similarly Bertha Gray Hayes in the 1940s created overshot designs with fewer threads than in traditional patterns.
Then I went to my personal library. Many of the designs in A Handweaver's Pattern Book by Marguerite Porter Davison, chapters 13, 15, 17 and maybe others are examples of these smaller designs. In her book Weaving Overshot: Redesigning the Tradition, Donna Sullivan shows examples of miniatures by both Estes and Hayes. In her section on altering scale, she refers to many patterns already reproduced in miniature, and then describes the process of reducing the size of a pattern by removing pairs of threads. Carol Strickler, in A Weaver's Book of 8-Shaft Patterns: From the Friends of Handwoven , gives a rule of thumb for miniaturizing overshot. Whether reduced from a larger design or made "from scratch" by using shorter blocks, the miniature draft ends up as Barrett describes as point and progressing twill threading. A final clue comes from Estes, where she says a design has been miniaturized when it has been reduced to the point where it cannot re reduced further without losing the character of its pattern form.