Puzzled by a new result on neutrino speeds

Let's turn it around and ask a different question. Is there another direct measurement of the neutrino speed that sets such a tight limit? (Admittedly, the directness is contingent on the coincidence representing both a common source and negligible delay between the gammas and the nus at the source, but just taking that as a given arguendo.)

It might be significant in that sense even if the mass limit set is rather uninteresting.

And indeed, the authors write in the summary

We showed that significant improvements can be obtained on limits on the neutrino velocity, the violation of Lorentz invariance, and the accuracy of the EEP, by using the observed time delays between the neutrinos and photons.

They also discuss some other limits that are set by the measurement (I think they are taking the conditions above as a given here, though I haven't read in enough detail to be sure).