Doctrinal writing uses a small technical vocabulary very heavily, and Buddhist Sanskrit is an extreme case. A handful of terms carry most of the conceptual weight, each generating compounds, derivatives and technical senses, and a page of argument may return to the same three or four roots dozens of times.
That has a visible effect on a Siddham page. The letters and clusters that open the central terms recur far above their frequency in the language at large, and a reader develops an eye for them: the shape at the front of the word for the teaching, the cluster at the front of the word for knowledge, the syllables that open the terms for suffering, impermanence and the absence of self. Identifying the subject of a page precedes construing it.
The word dharma is the hardest case for anyone reading in translation, because it has a wide range of senses even inside one school and a wider one across them: the teaching, the truth, a duty, a phenomenon, an element of experience. Translators have used a dozen English words for it and none of them covers the range.
The atlas records the term and its sources rather than choosing among the readings, and where the schools take genuinely opposed positions on what it means, that disagreement is itself part of the record.