The paper has been discussed after the rebuttal that the reviewers found useful and actionable (e.g., clarification about the novelty of the proof and about the experiments). The paper is recommended for acceptance. All reviewers have acknowledged that the paper makes a step towards better understanding over-parameterization and the implicit bias of gradient descent. As promised in the rebuttal, it is important to include in the final version of the paper the mentioned clarifications and discussions.