Photo: Wikimedia Commons · CC BY 2.0
Thesis
The common mistake is to lift “规一曰模一曰棬以铁制之或圆或方或花” out of its sentence and turn it into an absolute rule.
Text
“The gui mold, also called mo or quan, is made of iron, in round, square, or floral shapes.”
Context
规：压饼的模具，又叫模、棬（quān）。以铁制成，有圆形、方形、花形。
Evidence
- Collation: 各本一致。吴觉农注：唐代饼茶以"规"定型，圆者为"月团"，方者为"小方"，为后世团茶（龙凤团茶）之先声。
- Existing readings: 吴觉农指出"规"即压茶模具：唐饼、宋团、明清砖沱，皆由此演化；"或圆或方或花"说明唐代饼茶形态已多样，不只是圆饼一种。
Analysis
The usual misreading extracts “规一曰模一曰棬以铁制之或圆或方或花” as a slogan. 各本一致。吴觉农注：唐代饼茶以"规"定型，圆者为"月团"，方者为"小方"，为后世团茶（龙凤团茶）之先声。 In fact every judgment in the chapter carries a limit of place, season and use.
Conclusion
The section does not give a universal rule. It demonstrates a method: read the text, the annotation and the Tang context together before making a modern claim.
Source: The Classic of Tea, Chapter II · The Implements, section 5; the original is in the public domain.
When lost, brew a cup first.