Right, that works, we could just drop \gamma_0 \cup \zeta_0 from N. I don’t think it actually simplifies the proof though, because the reasoning for the first segment (now from (0,0) to P(\gamma_1 \cup \zeta_1)), would still be distinct from that for the other segments.
Consider the following:
- 3 transactions A (fee 0), B (fee 3), C (fee 1), all the same size.
- L_1 = [A,B,C], chunked as [AB=3/2, C=1/1]
- L_2 = [B,A,C], chunked as [B=3/1, AC=1/2]
- L_2 is a strictly better linearization, the fee-size diagram is higher everywhere.
- The feerate (using the R(\gamma_i) method) for the middle byte is 3/2 for L_1, but 4/3 for L_2. Would they be considered incomparable by the feerate-size diagram?