on the other hand, play a role in interactions, which would be in accordance with their interpretation as measurable quantities, as measurements always go along with some interactions. Due to the exchanged roles of $(E,\vec p\,)$ and $(\varepsilon,\vec\pi)$ in relation to the common DSR interpretation, reaction thresholds anomalies would be equally small as in usual DSR, but in the opposite direction. For example, when conventional DSR predicts an insignificant lowering of the GZK cutoff [@SM], the reversed interpretation would lead to an (equally insignificant) raising. (Recent observations do not seem to confirm a shift of the GZK cutoff at all [@GZK].)\
[**Acknowledgement**]{}. Supported by the Ministry of Education of the Czech republic, contract number MSM 0021622409. The author thanks the Perimeter Institute for warm hospitality and support and S. Hossenfelder and K. Bering for helpful discussions.

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