Two very different situations live here, because the tracks differ:
There is no revision round at ICALP (unlike a journal), so the response is your one and only chance to speak — and it can only move a paper by fixing misreadings and correctness doubts, never by arguing taste.
A rebuttal moves a borderline paper when it:
It does not move a paper when it:
[Correctness doubt] a reviewer questions a specific step -> HIGHEST priority: resolve it exactly
[Misreading] a reviewer misstates what you proved -> correct crisply, cite the line
[Missing comparison] "how does this compare to [bound]?" -> give the one-sentence comparison
[Significance/taste] "not surprising / incremental" -> brief, factual context; do not litigate
[Genuine gap] a real hole they found -> concede honestly; state what survives
Spend your limited words on correctness and misreadings, which you can actually change, not on significance debates, which you usually cannot.
Because there is no revision round, a real proof gap is usually fatal — but a misperceived gap is very much winnable:
If Track A reaches out about correctness, treat it like a focused Track B correctness answer: address only the step in question, point to the proof, and provide the missing detail. Do not use it to argue significance or add new claims.
Summary (2-3 sentences): what we clarify, and the one correctness point we resolve.
Reviewer 1
- [Correctness] Concern about Step 3: <exact hypothesis/lemma/line that answers it>.
- [Misreading] R1 states we assume <X>; we assume <Y> (Def 2). Consequence: <...>.
Reviewer 2
- [Comparison] vs the bound of [ref]: <one-sentence comparison>.
- [Clarification] <the requested constant / boundary case>.
Reviewer 3
- [Conceded] The gap in Lemma 6 is real; Theorems 1-2 are unaffected; Cor 3 weakens to <...>.
[Track] B (rebuttal window) / A (correctness contact only)
[Triage] correctness doubts / misreadings / comparisons / taste / real gaps — counts
[Priority answers] the correctness/misreading points that can actually change the decision
[Concessions] real gaps, stated honestly, with what survives
[Anonymity] response free of identifying info? yes/no
[Forbidden] new theorems / taste arguments / promised-but-unwritten proofs — present? remove