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Thesis
Read through modern tea science, “凡煮水一升酌分五碗乘热连饮之以重浊凝其下精英” is not a lab result but a set of variables: cultivar, soil, light and plucking standard.
Text
“For each sheng of water, divide it into five bowls and drink while hot, in succession. The heavy and muddy settles below; the essence and fineness floats above.”
Context
酌分五碗：一升水分五碗。乘热连饮：趁热连着喝。重浊：厚重浑浊的部分。精英：精华。
Evidence
- Collation: 各本一致。吴觉农注："重浊凝其下，精英浮其上"道出茶汤分层之理。
- Existing readings: 吴觉农指出"乘热连饮"是陆羽的饮茶要领：热饮则精华在口，凉则精英散而浊味现——今人"茶要趁热喝"的老话，正源于此。
Analysis
Modern tea science would split “凡煮水一升酌分五碗乘热连饮之以重浊凝其下精英” into cultivar, soil, light and plucking variables. 吴觉农指出"乘热连饮"是陆羽的饮茶要领：热饮则精华在口，凉则精英散而浊味现——今人"茶要趁热喝"的老话，正源于此。 They remain testable, but only with their conditions attached.
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 V · The Brewing, section 7; the original is in the public domain.
Experience should be explained, not mystified.