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Thomas Kuhn's account is a useful corrective to a history in which scientists simply accumulate observations and replace theories whenever a contrary observation appears. It is less convincing as an exceptionless sequence governing every science. Its compatibility with scientific progress depends on what progress means.

In normal science, a community shares a scientific paradigm: exemplary achievements, accepted instruments and standards for choosing tractable problems. An unexpected result can initially be treated as a problem in the calculation or apparatus. This need not be irrational. A framework that succeeds elsewhere gives investigators reasons to check an instrument before abandoning the framework. Revolutionary theory change reorganizes some of those commitments instead of merely adding another measurement.^[ref]

The important contrast is between a descriptive account of how research is organized and a justification of every community's decision. Shared training can explain persistence without making persistence correct. A contrary experiment can expose a failed auxiliary hypothesis, but it can also expose a central error. The Duhem problem rules out an automatic inference from one anomalous reading to one uniquely false theory; it does not authorize indefinitely protecting a theory from independently calibrated tests.

Nor does incommensurability require complete inability to compare. Theories can change the meanings of such quantities as mass while still being compared through specified apparatus readings, limiting calculations and predictions. For instance, the relativistic energy of a free massive particle has the expansionAt $p\ll mc$, subtracting the rest energy leaves the familiar leading kinetic energy. This is an explicit connection between domains, not an assertion that every concept remained unchanged. It gives a concrete way to retain successful calculations while recognizing the earlier theory's limitations.

Progress measured as closer approach to a single final ontology is therefore not guaranteed by the historical pattern alone. Progress measured through more accurate prediction, solving independently specified problems and understanding why older models work in restricted domains is compatible with substantial conceptual change. These criteria must not be defined merely as whatever a victorious community happens to prefer.

Finally, different specializations can develop competing frameworks simultaneously. A research community need not occupy one uniform stage, and a chronological label alone does not demonstrate a crisis or revolution. The strongest use of Thomas Kuhn's account is consequently comparative: identify what changed in examples, standards and practice, then ask which changes improved scientific capacities. It explains important features of research without supplying a universal historical law or implying that all theory choices are equally good.