On the significance of radiation reaction R. Holtzapple, C. F. Nielsen, A. H. Sørensen, U. I. Uggerhøj and CERN NA63 Eur. Phys. J. D, 76 9 (2022) 167 Published online: 20 September 2022 DOI: 10.1140/epjd/s10053-022-00496-2