The two tape presentations are compiled into one another. If $T$ and $Q$ are the source time and sufficient-width polynomials, the arena-to-native translation uses time $66*T + 6*X + 81$ and width $Q + 7$; the native-to-arena translation uses time $18*T + 26$ and width $Q + 7$.

Thus a nonconstant time degree is preserved, while arena-to-native conversion can raise degree zero to degree one because the current adapter buffers the input in linear startup time. Width degree is unchanged for nonconstant $Q$. Each implication chooses its own witnesses: this theorem neither states nor uses equality of polynomial degrees across the two directions.