The most-repeated correction in the Kronos record is never that the math was wrong; it is that a basis was silent. The remedy, applied consistently, is to declare the assumption — the helium ash fraction, the confinement factor, the cost-recovery factor — so any change moves by recorded restatement.
An audit of the breeder's gain found it rested on an undeclared ash fraction — the same silent-basis defect that had moved earlier frozen values. The arithmetic was correct; the problem was that the basis was not stated. The fix was to write f_He4 = 0.05 (Z_eff 1.158) into the entry, not to change the number.
A declared basis converts a hidden assumption into a testable one. If a later determination disagrees, the value moves by recorded restatement rather than silent change — and reviewers always know exactly what each number is conditional on. Declaration is the whole discipline.
| Recurring defect | silent basis (not bad math) |
| Remedy | declare the assumption |
| Examples | ash fraction, confinement factor, CRF |
| On change | recorded restatement |
| Result | assumptions testable |